ISO for 2015-08-21

[Harald Sitter]

http://files.kde.org/snapshots/unstable-amd64-latest.iso.mirrorlist

Final testing ISO for 5.4; probably switching back to master builds in
the next ISO. Builds are as of yesterday morning.

# changes
- whole slew of packaging improvements

# errata
- kontact packaging seems a bit broken and doesn't install; pending
investigation still
- due to the ongoing gcc5 transition it is entirely possibly that
you'll find a gcc5 related crash

# random ISO notes
- this ISO has a special repository enabled that has virtually no QA
applied to it as some gcc5 bits are waiting there for issues to
resolve. it is therefore not advisable to use an installation from
this ISO for longer than absolutely necessary. some package will break
... eventually.