Added usage of OO model as library
Applied libmagic for image file recognition
refs #712
Deleted library manager (minor breakage)
refs #712
Fixed album view
refs #712
Added photo ids
Reintroduced library category name generation
refs #712
Fix unattached label in photo tile
refs #712
Merge branch 'master' into photo-detection

Conflicts:
	pisak/viewer/app.py
	pisak/viewer/widgets.py
refs #757
Disable incompatible code in pager
Fixed photo selection
Cleaned up viewer app.py
refs #757
Set tile size first then load photo
refs #757
Load tile preview at default size if not supplied with any
refs #757
Fixed binned label in photo tile
refs #768
Add filler actor in _Page class
refs #770
Merge branch 'master' into photo-detection

Conflicts:
	pisak/viewer/app.py
	pisak/viewer/widgets.py
refs #770