Visual Basic Incompatibility in Mutating Methods

Visual Basic compiler does not emit `hidebysig` for methods, which causes `AssemblyAmender.Mutate(MethodBody)` to miss them.

_description provided here is quoted from http://msdn.microsoft.com/en-us/library/system.reflection.methodbase.ishidebysig%28v=vs.110%29.aspx_

>When a member in a derived class is declared with the C# new modifier or the Visual Basic Shadows modifier, it can hide a member of the same name in the base class. **C# hides base class members by signature.** That is, if the base class member has multiple overloads, the only one that is hidden is the one that has the identical signature. By contrast, **Visual Basic hides all the base class overloads.** Thus, **IsHideBySig** returns **false** on a member declared with the **Visual Basic Shadows** modifier, and **true** on a member declared with the **C# new modifier**.