Moved classes from reddav.php into own files.

Finished moving classes out from include/reddav.php into own files. Also
continued with namespace for RedDAV.
Improved some docs and added some todos and fixmes.
content deletion issue
fix connedit > collection > checkbox position
A fix, but I have no case to verify.

I could not find out under which conditions this is relevant and therefore have no test case, but it must be of instance RedDAV\RedFile.
cleanup of sync_locations and better logging. There was one significant code change but it is unrelated to current issues, basically if no primary was set we were setting everything as primary.
Merge https://github.com/friendica/red into pending_merge
Merge pull request #636 from dawnbreak/RedDAV

Moved classes from reddav.php into own files.
bit of cleanup of hidden_configs. This is a start - we've got hundreds more.
Merge https://github.com/friendica/red into pending_merge
diaspora_send_status() - recalculate markdown translation to pickup any later message changes after original submission like wall-to-wall attributions for instance. Normally this would've come from our cached version which was stored prior to tag_deliver being run and therefore isn't yet aware that wall-to-wall status may have changed after delivery.
context check
fix connedit > collection > checkbox position also for webkit - this will need a better solution though
bring back PM upload functionality and why oh why are we still loading tinymce?
Merge https://github.com/friendica/red into pending_merge
tinymce still seems to be referenced. Can't quite get rid of it.
really fix connedit > collection > checkbox
Merge branch 'master' of https://github.com/friendica/red
Merge from origin