New specs for sermon added.
Test's name changed to represent it's behavior correctly.
New specs to check image format added for photos.
Syntax improved in specs.
Small improvements.
Refactoring: removing useless variables.
Article's specs for controller: put, destroy, create specs + new hash syntax + `let` instead of before each.
Album's specs for controller: new hash syntax + `let` instead of before each.
Contacts spec refactored: new hash syntax, duplication removed via shared_examples, test for updating, let instead of before each.
HomesController's specs updated: new hash syntax, let instead of before each.
PhotosController's specs updated: new hash syntax, let instead of before each.
SermonsController specs updated: new hash syntax, let instead of before each.
StatsController specs updated: new hash syntax, let instead of before each, duplication removed via shared_examples.
WelcomeMessagesController's specs added.
Unifying shared_examples names.