Using @Arg alone causes RuntimeException

Using @Arg alone with a call to Akatsuki.restore and a non-null instance state causes Akatsuki to look for the @Retained's retainer class which does not exist.

This has to be implemented in the generated code(a.k.a compile time) otherwise an annotation query has to be done to distinguish which annotation type is actually being used. Android seems to have questionable performance when it comes to runtime annotation queries so this fix ill be implemented via CLASS_LUT and a runtime fall-back in case the LUT option is turned off