Specification Update

• Fixed a bug where classes, structs or interfaces that have no declared schema fields were allowed to be added to the schema as non-leaf graph types in some edge cases. [§3.6][§3.7][§3.10]

Validation Improvements

• Added a rule to exclude any implicitly discovered fields that accept, as an argument, or return as a value a delegate.
• Added a specific error message when attempting to use a delegate (or Func<>, Action<>) as an argument to an explicitly declared field.
• Fixed a bug where an argument to a controller action or POCO field would not validate its type in some circumstances.
• Fixed a bug where a class or interface with overloaded methods would throw a declaration exception even when 0 or 1 of those methods would be added to the schema. An exception will still be thrown if both attempt to be added (i.e. duplicate field names).
• Fixed a bug where inherited methods or properties of Object or ValueType may be parsed by the templating system in some cases.
• Improved the error messages for some argument type validation failures such that the the owner of the argument will now be named for easier identification.
• Improved the error messaging to properly identify which controller, object or interface was being parsed when a required dependent type fails to validate.

Related PRs: #128