Add SRG-name based Access Transformer base class

Requested by @cpw

Uses runtime deobf info for allowing SRG name
modifiers to allow version-independent access level
changes.

This version was implemented separately originally to avoid LGPL code in a non-LGPL mod, so it has a different configuration format from the standard AT.

Code similar to the main function in AccessTransformer.java, with the addition of setup for FMLDeobfuscatingRemapper will allow this to be used at FML/Forge setup time.

In terms of functionality, the main difference is running all names (Class/Field/Method) through FMLDeobfuscatingRemapper prior to comparing them with the configured information.