- Implemented some addition to support async await methods with returntype like Task<ActionResult>
- Added specs for making sure actions returning Task<ActionResult> can be configured.
- Added extension IsControllerActionReturnType for checking if a type is a controller action return type.
- Modified specs and fixed issue with configuration methods not finding controller actions returning Task<T> where T is not ActionResult.
- Added specs for the IsControllerActionReturnType extension.
- Prepared for removal of System.Web.Mvc dependency in the FluentSecurity.TestHelper project.

- Removed ActionResult contraint for For<TController> in PolicyExpectations.
- Removed For<TController, TResult> in PolicyExpectations as it was not longer needed.

- Removed ExpectationExpression<TController, TResult>.
- Removed ActionResult contraint for expression passed to constructor of ExpectationExpression<TController>.

- Removed IController constraint for Expect<TController> in PolicyExpectationsExpression.
- Removed ActionResult constraint for Expect<TController> in PolicyExpectationsExpression.
- Removed overload for Expect and Exprect<TController> that was used for Task<ActionResult> expressions in PolicyExpectationsExpression.

- Removed IController constraint for Verify<TController> in SecurityConfigurationExtensions.
- Removed unused references from FluentSecurity.TestHelper project.
Merge branch 'feature-async-controllers' into develop