Finish and Merge ISerialize branch into master

[wvdvegt]

The ISerialize branch is a fix for some IL2CPP regarding the use of generics in the ISerializer interface.
IL2CPP tends to strip the method when converting IL to CPP during Unity3D code optimization.

Solution is to remove the generic from the Deserialize method, so:

object Deserialize<T>(string text, SerializingFormat format);

is changed into:

object Deserialize(Type t, string text, SerializingFormat format);

The code of the ISerializer.cs and the GameStorageClientAsset.cs have already been changed in the ISerialize branch but needs testing.