Finishing up widescreen patch support: Add GUI toggle and connect it.

git-svn-id: http://pcsx2.googlecode.com/svn/trunk@5716 96395faa-99c1-11dd-bbfe-3dabce05a288
Uploading all patches from the PS2 Widescreen Pack dated 08-11-2013. 
Patches contributed by members of the community and assembled by devina40. 
Thanks people! :)

It's currently untested if the patches play nicely with regular cheats, will do that later.

git-svn-id: http://pcsx2.googlecode.com/svn/trunk@5717 96395faa-99c1-11dd-bbfe-3dabce05a288
gsdx ogl: Used a basic flat interpolation for color interpolation (line & tri primitives)

Card that support gs:
remain only a gs to generate sprite from a line. Even dummy gs are costly for the GPU.

Card that don't support gs:
remove useless copy of color for line and triangle primitives

Note for dx: opengl 3.2 (maybe not gles) supports both flat interpolation
convention (GL_FIRST_VERTEX_CONVENTION or GL_LAST_VERTEX_CONVENTION).  It might
be possible to shuffle vertex index to put the last vertex in first position.

- buff[0] = head + 0;
- buff[1] = head + 1;
- buff[2] = head + 2;
+ buff[0] = head + 2;
+ buff[1] = head + 1;
+ buff[2] = head + 0;



git-svn-id: http://pcsx2.googlecode.com/svn/trunk@5718 96395faa-99c1-11dd-bbfe-3dabce05a288