Fix, update and add some network specific logos as seen on the home page in "poster" view mode.
Merge pull request #601 from adam111316/network_image_renaming

Renaming network logos files to lowercase as SR requires lowercase
Merge pull request #594 from JackDandy/NetworkLogos

Network logo changes
Fix for nullhandler issues for py2.6 users,
Fix for rsstorrents.
Fix for failed download handling and sql issues
Fix for scene exception update error, please delete cache.db file for this to fix tow take affect.
Merge remote-tracking branch 'remotes/upstream/dev' into testing2

Conflicts:
	sickbeard/databases/cache_db.py