Change 'isGranted' view helper config.

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

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

Change 'isGranted' view helper config.
Update composer.json to track ZF master

2.1 is now in master so we can stop tracking the develop branch. Yay!
Merge pull request #42 from davidwindell/patch-3

Update composer.json to track ZF master
Update composer
Merge pull request #44 from bakura10/update-composer

Update composer