Fix building with Qt 4.7

For reasons unknown, qPrintable() doesn't work with QByteArray in Qt versions
prior to 4.8 (the confusing thing is why it works now, in fact). In any case,
it probably makes sense to print a binary blob using normal QDebug output for
QByteArrays anyway, rather than trying to convert it to a string.
Fix lag display

Not sure what I was thinking in d3ce95c, but that commit
a) didn't fix compiling with Qt < 4.7
b) confused local time and UTC, which
c) completely bugged lag display.

Should be working now.
Simplify and fix (re)connection logic

Still a mess, but the refactor is right around the corner anyway. Now at
least Quassel should no longer reconnect automagically if disconnected
explicitly.
Fix missing #include
Build against Qt 4.6 again

Bah.
Change date/time formats

As some date strings are generated core-side, and servers might have set
a different locale than connected clients, we would like to avoid localized
date strings. As Qt4 also doesn't allow to display a time zone (offset) without
also localizing the string, we convert all core-side times into UTC and display
them in ISO format.

The daychange message, however, is generated client-side and thus can be shown
according to application or system locale.
 we would like to avoid localized
dates
Update "About" dialog

New contributors!
Bump version.inc for release
Post-branch version bump
Add old-style com.trolltech annotations back into dbus xml files

Looks like the move from com.trolltech to org.qtproject happened only
recently, and with older Qt point releases Quassel will fail to build
that way.

By specifying both annotations, we hopefully silence the warnings in
current Qt while keeping Quassel buildable against older Qt.
Update translations from Transifex

Newly added languages: Esperanto (eo), Lithuanian (lt), Romanian (ro) and
Serbian (sr)

Many thanks to:
 - cs: Vít Pelčák <vit@pelcak.org>
 - de: ToBeFree <tobias@freiwuppertal.de>
 - eo: cordata <tiffypet@yahoo.com>, <recoverybenk@gmail.com>
 - es: Adolfo Jayme Barrientos <fitoschido@gmail.com>, enjolras <yo@miguelrevilla.com>
 - fi: Larso <larso@gmx.com>, Lasse Liehu <lasse.liehu@gmail.com>
 - lt: Liudas Alisauskas <liudas@akmc.lt>
 - nb: sandsmark <sandsmark@samfundet.no>
 - ro: Sergiu Bivol <sergiu@ase.md>
 - ru: sfionov <fionov@gmail.com>
 - sr: Jovan Jojkić <jovanjojkic@gmail.com>
 - tr: Volkan Gezer <volkangezer@gmail.com>
 - tr: zeugma <sunder67@hotmail.com>
 - uk: Yuri Chornoivan <yurchor@ukr.net>
update translation template - adds 15 new strings
Update about dialog once again for new translations
Finally fix reconnection logic

Really, that part of the code needs a good old refactoring.
Update ChangeLog