General fixes to make things work

* Change albumArtCache.py to use proper python pep8 stylings
* Fix regression in AlbumArtCache to stop iterating non-stop
* Adapt classes to changes in albumArtCache.py
* Fix Minor styling issues
* Fix LoadMore Button behaviour
Fix pep8 issues
pep8: remove whitespace
Merge pull request #29 from gnome-prototypes-team/fixes1

General fixes to make things work
widgets: Add missing parameter in a callback
Minor pep8 adjustments and small cleanup in application.py to not
force the window to show all its widgets
Merge pull request #31 from gnome-prototypes-team/fixes1

Minor pep8 adjustments and small cleanup in application.py to not
Merge pull request #30 from kyoushuu/master

widgets: Add missing parameter in a callback
widgets: correctly init widgets
view: set title and visible child correctly
albumArtCache: temporary fix callback