move to README.md, update platform list

INSTALL

@@ -2,8 +2,8 @@
 ----------------
 
 You will need an entropy (randomness) source.  If your OS has arc4random or
-getentropy then that is ideal. Otherwise, you can use the builtin arc4random
-implementation or the one built into LibreSSL.
+getentropy then that is ideal. Otherwise, OpenNTPD will use its builtin
+arc4random implementation, which is also part of the LibreSSL project.
 
 2. Building / Installation
 --------------------------
@@ -128,4 +128,4 @@ configuration file uses a selection of publicly accessible "pool" servers
 ------------
 
 If you experience problems compiling, installing or running OpenNTPD,
-please report the problem to the address in the README file.
+please report the problem to the address in the README.md file.

Makefile.am

@@ -18,7 +18,7 @@
 SUBDIRS = include compat src
 ACLOCAL_AMFLAGS = -I m4
 
-EXTRA_DIST = VERSION ntpd.conf
+EXTRA_DIST = README.md INSTALL VERSION ntpd.conf
 
 install-exec-hook:
 	@if [ ! -f "$(DESTDIR)$(sysconfdir)/ntpd.conf" ]; then \

README

@@ -1,35 +0,0 @@
-This is a new port of OpenBSD's native ntpd to other Unix flavours adding
-autoconf support and the necessary compatibility layer.  It is based on
-portability code from the OpenSSH and LibreSSL portable projects.
-
-OpenNTPD has a web site at http://www.openntpd.org/
-
-The current portable tree can be found at https://github.com/openntpd-portable
-
-Platform Requirements
----------------------
- - adjtime(2) and settimeofday(2) syscalls or equivalent.
- - adjfreq(2) or an equivalent compatibility function for best results
- - daemon(3), setresgid(2), setresuid(2) or equivalent
- - A working arc4random(2) implementation, OpenSSL or LibreSSL
-     (this project shares the same arc4random compatibility code from LibreSSL)
- - libtls (included with LibreSSL 2.1.4 or higher) is required for HTTPS time
-   constraint validation.
-
-At the time of writing the Portable version is known to build and work on:
-
- - OpenBSD (5.6)
- - Linux (Ubuntu 12.04, 14.04)
- - FreeBSD (9.x, 10.x)
- - NetBSD (6.1.5)
- - Solaris (10.x, 11.x)
- - Mac OS X (10.9)
-
-OpenNTPD may work on other operating systems, newer and older, but the above
-ones are tested regularly by the developer.
-
-Reports (success or otherwise) are welcome. You may report bugs or submit pull
-requests at the GitHub project: https://github.com/openntpd-portable
-
-Thanks,
-  Brent Cook <bcook at openbsd.org>.

README.md

@@ -0,0 +1,25 @@
+This is the portable version of OpenBSD's native Network Time Protocol daemon,
+OpenNTPD http://www.openntpd.org/
+
+## Platform Requirements
+
+ - adjtime(2) and settimeofday(2) syscalls or equivalent.
+ - adjfreq(2) or an equivalent compatibility function for best results
+ - daemon(3), setresgid(2), setresuid(2) or equivalent
+ - a working arc4random(2) implementation (this project shares the same
+   arc4random compatibility code from LibreSSL)
+ - libtls from LibreSSL 3.0+ is required for HTTPS time constraint validation.
+
+## Supported Operating Systems
+
+OpenNTPD may work on other operating systems, newer and older, but the above
+ones are tested most recently by the developer. At the time of writing,
+OpenNTPD portable is known to build and work on:
+
+ - OpenBSD (6.7)
+ - Linux (Debian 10+, Ubuntu 18.04+)
+ - FreeBSD (12+)
+ - MacOS (10.13+)
+
+Reports (success or otherwise) are welcome. You may report bugs or submit pull
+requests at the GitHub project: https://github.com/openntpd-portable