added AT-Platform esque returning mouse pointer
refs #607
fixed AttributeError
refs #607
Slides created dynamically by slides source
Funcs for getting pending, current, previous or next slide
Decreased number of args in couple of funcs
Images loaded asynchronously
refs #614
remove photo buffer loading for all pics - needed only for edition
refs #623
delete hard_coded photo_path jagoda.jpg from photo_edition.json - fix
Merge branch 'master' into returning-mouse
Photos loaded no asynchronously
refs #614
Merge branch 'master' into slides-loading

Conflicts:
	pisak/viewer/widgets.py
Merge branch 'master' into returning-mouse
add mouse selection as a default in branch-master
add another unwind-to prop - minor fix
Replaced not used data loader with lib manager
Applied docs and resigned from lambda handler due to code review
Applied lib manager to the slides source in viewer widgets
refs #614
Added docs to viewer widgets methods
Applied previously omitted pep8
refs #614
Favourite photos management
Added handlers for adding and removing from favs
Added sqlalchemy based database system for storing fav photos paths
Added funcs for addinf, removing, getting all and checking if is in fav photos
Deleting from favs db if file doesn't exists
refs #663
Removed unwind to property from scan group in json
Hover button color as in the project
refs #646 #445
Text documents with sqlalchemy and xdg
New module for documents management
Updated handlers and widgets
refs #620
Add document to database not returning path
refs #620
pep8-ed library_manager.py
refs #663
Merge branch 'master' into favs
Merge branch 'master' into slides-loading