A method configured with Invokes now returns default value for return type when invoked.
(Rather than throwing a NullReferenceException when the return type is a value type.)
Fixes #114.
using FluentAssertions for tests
Merge pull request #187 from blairconrad/114-invokes-squashes-default-return-value

the shape of a possible fix for #114, just for discussion
refactor helpers to be extension methods
#218 switch sl50 assembly from Castle.Core sl40 to sl50
switched to FluentAssertions and 3A's
Merge pull request #226 from adamralph/refactor-helpers

refactor helpers to be extension methods
Merge pull request #227 from adamralph/218

#218 switch sl50 assembly from Castle.Core sl40 to sl50