Change 'isGranted' view helper config.

Remove 'helper_mapper' key from 'view_manager' config. Rename 'isGranted' factory in 'getViewHelperConfig'.
Merge pull request #38 from jmleroux/config

Configuration file sample
Merge pull request #36 from francisdaigle/master

Change 'isGranted' view helper config.
unit tests
Merge branch 'master' into identity
Merge branch 'master' into dev
Merge branch 'identity' into dev
ZendDb providers with tests
merge branch 'provider' into dev