VideoCommon: rewrite DataReader
VideoCommon: fifo cleanups
VideoCommon: cleanup OpcodeDecoder
VertexLoader: Move the old Datareader function into VertexLoader
VideoCommon: Rename s_pCurBufferPointer
VideoCommon: clean up VertexLoader
UnitTests: fix VertexLoaderTest
Merge pull request #1609 from degasus/datareader

VideoCommon: Datareader