New files added to CMakeLists.txt
Started take() method implementation, moved preferences and its enumerations to the separate nested struct.
Added QDomElement-to-Preferences parsing into the nested Prefereices structure.
Removed useless tails from the XEP-0136-meta branch changes commited there by mistake.
Few small improvements.
Removed monstrous static conversions from Preferences.
Added writePrefs into Preferences, so callers need no DOM_FORAECH anymore.
Implemented handleSet and handleResult for respective <iq> types.
I decided not to store any setting inside an archiving task, let the main app handle them.
Variables are now replaced with corresponding signals.
Moved Preferences structure to the separate file in jt_archive directory.
Started initial test build, but some enumerational intersection must be solved first.
Continuing fixing build errors.
Enums were removed, switched to QString.
Project is now buildable, initial testing is required next.
jt_archive helpers are now static.
Added archiving NS to the features list.
Added XEP-0136 configuration into account settings UI.
Added JT_Archive signals for preference changing.
Merge branch 'XEP-0136-no-enums' into XEP-0136-meta
Project now uses Qt metasystem to convert string into enums.
Account configuration dialog is now able to show received archiving settings.
Conflicts:
	protocols/jabber/tasks/jt_archive.cpp
	protocols/jabber/tasks/jt_archive.h