Win32: Change --gfx to --graphics (and its suboptions) to be consistent with Headless.
Also, software force-activates OpenGL mode, since it does not work with Direct3D currently.
Thanks to @unknownbrackets for the suggestions.
Make the D3D backend cmd processing work more similar to the GL backend
Make D3D TransformDrawEngine more similar to GL
Move most GL code out of GLES/SoftwareTransform.cpp
Cleanup SoftwareTransform a bit more
Move GLES' SoftwareTransform to Common
Replace the DX9 software transform code with the new common one
Fix burnout depth issue by dirtying the proj matrix on viewport change
Merge pull request #6896 from hrydgard/gpu-convergence

GPU Convergence - more work on bringing the D3D and GL backends closer
Move spline generation to SplineCommon, make SplineDX9.cpp identical to Spline.cpp (merge later somehow)
Do not need to ask directory when build Android
Merge pull request #6897 from sum2012/Android-build

Do not need to ask directory when build Android
More convergence (tex stuff)
d3d: Correct framebuffer sizing issues.
d3d: Set texture only when enabled.

This allows optimizations that were applied to the cmd flags.
dx9: More execute functions
Only show the graphics API on the title screen in Windows
Merge pull request #6899 from unknownbrackets/gpu-convergence

d3d: Set texture only when enabled
Merge pull request #6900 from hrydgard/gpu-convergence-2

Gpu convergence 2 - break out much of the Spline code into GPU/Common, fixes some minor things
d3d: Support offset rendering.