Add a better layout and theme for the message list so it's more ergonomic
Closes #8
See merge request dystopia-project/simple-email!12

This is to close #8 issue.
The new interface is much more "material" and ergonomic.
The sender is displayed (either compact or with full address) below.
Then, a quick & small email summary is shown.
The thread message count is only displayed if there is more than a single message.
I'm using light font here, and the same color for both unread & read messages. Unread messages are using bold font.

closes: #10

Currently translated at 99.2% (241 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/nl/

## [1.2.1](https://framagit.org/dystopia-project/simple-email/compare/v1.2.0...v1.2.1) (2018-11-23)
### Bug Fixes
* check compatibility on notification settings ([36b3e25](https://framagit.org/dystopia-project/simple-email/commit/36b3e25))
* crash on public notification without color ([4bc5d9a](https://framagit.org/dystopia-project/simple-email/commit/4bc5d9a))

prepare 1.2.1
See merge request dystopia-project/simple-email!11

Correct typo
See merge request dystopia-project/simple-email!10

Currently translated at 84.8% (206 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/nb_NO/

Currently translated at 84.4% (205 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/nb_NO/

Currently translated at 99.2% (241 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/en/

Currently translated at 82.3% (200 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/nb_NO/

Currently translated at 79.8% (194 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/nb_NO/

Currently translated at 17.7% (43 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/vi/

Currently translated at 84.0% (204 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/tr/

Currently translated at 94.7% (230 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/sv/

Currently translated at 16.0% (39 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/sr/

Currently translated at 16.0% (39 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/ru/

Currently translated at 95.9% (233 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/ro/

Currently translated at 17.3% (42 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/pt_PT/

Currently translated at 39.5% (96 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/pt_BR/

Currently translated at 93.0% (226 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/pl/

Currently translated at 25.5% (62 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/fa/

Currently translated at 17.3% (42 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/nb_NO/

Currently translated at 17.7% (43 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/ko/

Currently translated at 17.7% (43 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/ja/

Currently translated at 95.1% (231 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/it/

Currently translated at 28.0% (68 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/hu/

Currently translated at 16.0% (39 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/he/

Currently translated at 17.3% (42 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/el/

Currently translated at 94.2% (229 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/de/

Currently translated at 96.3% (234 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/fr/

Currently translated at 17.3% (42 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/fi/

Currently translated at 95.5% (232 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/nl/

Currently translated at 54.7% (133 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/da/

Currently translated at 16.0% (39 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/cs/

Currently translated at 17.7% (43 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/zh_Hant/

Currently translated at 84.0% (204 of 243 strings)
Translation: SimpleEmail/Translations
Translate-URL: https://hosted.weblate.org/projects/simple-email/translations/zh_Hans/