test($translatePartialLoader): remove methods from provider

Remove methods urlTemplate() and useLoadFailureHandler() from provider
test($translatePartialLoader): cooperation with $translate + little fixes

Fix ResolveErrorHandler: resolve a promise with an object instead of a string
Move $httpBackend verifications to afterEach sections
Change coding style according to the jshint
Fix some logical errors in the "Error handling" section
Add "$translate service cooperation" section