Merge pull request #30 from neobrain/bitfield_work

BitField additions and fixes
[build] Search for the git binary in the default msysgit install dir

The Git for Windows installer doesn't add the Git binaries to the path
by default. (Due to risk of conflicts with built-in windows commands.)
Unless you have configured your system specially this causes the
scm_rev_gen.js script to fail to find Git.  Added more paths to the
script so that it searches in the default msysgit installation
directory, eliminating the need to set the PATH for most environments.
core: Kill off type redefenitions in armdefs.h
Merge pull request #33 from lioncash/redefs

core: Kill off type redefenitions in armdefs.h
Merge pull request #32 from yuriks/master

[build] Search for the git binary in the default msysgit install dir
GPU debugger: Don't keep track of debugging data if no debugger views are active.
Use a more compatible choice of initial framebuffer addresses.
GSP: Implement ReadHWRegs and WriteHWRegs properly.
GSP: HLE GXCommandId::SET_DISPLAY_TRANSFER and GXCommandId::SET_TEXTURE_COPY.
GPU: Add display transfer configuration.
GPU: Properly implement display transfers.
GPU: Add proper framebuffer register handling.
GPU: Emulate memory fills.
GPU: Initialize GPU registers to some sensible default state.
GPU: Interface cleanup.
Renderer: Add a few TODOs.
Renderer: Respect the active_fb GPU register.
Renderer: Fix component order in bottom framebuffer.
GPU: Make framebuffer code format-aware.
GPU: Make use of RegisterSet.