Merge pull request #1730 from hrydgard/vertex-loader

* Remove late accesses to attribute_config

* Refactor: Extract VertexLoader from command_processor.cpp.

Preparation for a similar concept to Dolphin or PPSSPP. These can be JIT-ed and cached.

* Move "&" to their proper place, add missing includes and make some properly relative.

* Don't keep base_address in the loader, it doesn't belong there (with it, the loader can't be cached).

* Optimize the vertex loader, nearly doubling its speed.

* Debugger fix

* Move and rename the MemoryAccesses class to MemoryAccessTracker.