srecord: new package

The SRecord package is a collection of powerful tools for manipulating
EPROM load files.

http://srecord.sourceforge.net/
msmtp: 1.4.30 -> 1.4.31

Also, set meta.platforms and fix meta.description (msmtp is not a MUA).
gtypist: update to 2.9.3 and fix the patch
vfdecrypt: fix source location
area53: fix source url
pyside-generatorrunner: fix version to match sources
boinc: fix url
mopidy: fix broken fetchgit -> fetchurl
libevent: Update to 2.0.21
opensmtpd: Update to 201307151923p1
nixUnstable: Update to 1.6pre3166_15e5ac8