Added deprecated flag for 'controllerFor' method on the 'ControllerMixin'.
Merge pull request #3448 from joelcox/controllerfor-deprecated-docs

Added deprecated flag for 'controllerFor' method on the 'ControllerMixin'
'Discreet' Typo
Merge pull request #3450 from flxf/discreet

'Discreet' Typo
Fix link to 'Contributing.md' to include file's name in README
Merge pull request #3451 from bantic/doc-fix-readme-link-to-contributing

Fix link to 'Contributing.md' to include file's name in README