added overload to Verify to accept Times as a Method Group
refactored Interceptor.Intercept to use a set of strategies. Function was broken in 8 separated strategies
Added an enum as a result of a single interception strategy to clarify when following action need to be executed
added remaining overloads to Verify
Merge pull request #34 from ChrisMissal/once

added overload to Verify to accept Times as a Method Group