Fix sceKernelSelfStopUnloadModule parameters

According to http://code.google.com/p/jpcsp/source/detail?r=3597
Correct sceKernelSelfStopUnloadModule 's name and logging
Use the debug interface to compare screenshots.

This way it's already implemented in all backends.
Centralize dx9 and gles headless stuff.

Well, could be cleaner, but this way all the comparison stuff works.
Workaround headless help not showing graphics.
Merge pull request #6809 from unknownbrackets/headless

Allow headless to compare Direct3D 9
d3d: Add basic stencil mask handling.

Mostly so we have it in dxstate, will probably reorganize stuff later.
Swap RGBA/BGRA when comparing screenshot data.
Oops, flipping was off by one.

That's why software and directx9 were off, arg.
armjit: Don't reset downcount on fpu instructions.

It's maintained always, oops.
armjit: Fix some downcount issues with rounding.

When setting the rounding mode we need to be super careful about not
destroying flags or R0 if they are needed.
x86jit: Fix some flags/EAX trashing in rounding.

Fixes #6810.
Eat cycles during block transfers.

Tests show this takes a number very close to 1.9 times the number of bytes
in cycles @222.

Using that value caused a tiny fps drop in one area of the God of War
demo, which may be correct but might also cause complaints.  A lot of our
other timing is not accurate, so using a lower value (1.6) to be on the
safer side.

This may cause things to reschedule more accurately when games drawsync,
and improves the gpu/commands/blocktransfer test.
Avoid some magic numbers.
Fix a type conversion warning.
Add block transfer to null gpu.

For tests, better to have it here.
Fix path issue running tests on Linux.

No trailing slash.  Doesn't hurt Windows to have an extra one.
Win32: Use wide strings to parse most command-line arguments.
Also do a tiny bit of cleanup in main.cpp (replacing strcmps with simple string equality checks).
jit: Update rounding mode immediately on ctc1.
GetWideCmdLine doesn't need to be exposed in the header anymore.
Also fix a warning.