Make Changes.rst nicer for 2.4 release

Make Changes.rst nicer for 2.4 release

- Add `` to all options
- Sort and group new features
- Group changes a bit better
- Fix some formatting/formulation

Patch V2:
- add missing quote, noticed by Samuli
- add new windows services
- add ECDH
- add pushable compression
- add Android and AIX platform support

Acked-by: David Sommerseth <davids@openvpn.net>
Message-Id: <1477060957-6423-1-git-send-email-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg12766.html
Signed-off-by: David Sommerseth <davids@openvpn.net>