ilist xml serialization

This is probably pretty self explanatory by reading the commits but here goes.

When a class declares a read-only property which is also a IList, ICollection then currently mono throws the exception

  ----> System.InvalidOperationException : To be XML serializable, types which inherit from ICollection must have an implementation of Add(System.String) at all levels of their inheritance hierarchy. System.Collections.Generic.IList`1[[System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]] does not implement Add(System.String).

this patch ensure that we do not try to get the TypeData of these Types which ultimately throws the exception.