Fix texture conversion shaders for GLSL ES.
Noticed this while messing with EFB to RAM.
We were having an implicit conversion from integer to float, GLSL ES doesn't allow implicit conversion.
Changes it to a explicit conversion to float.
Moves a few Cmake options so that debug options are near one another.
Moves GDBSTUB to the top as well where it should be.
Adds Link Time Optimization cmake option.

Adds a LTO option that isn't enabled by default.
Allows building release binaries with link time optimizations without generating a -dirty build.
Not enabled by default due to concerns of memory usage and increased build time.
Merge pull request #299 from Sonicadvance1/EFBRam-FixGLSLES

Fix texture conversion shaders for GLSL ES.
Merge pull request #301 from Sonicadvance1/LTO-option

Adds Link Time Optimization cmake option.
Workaround dumb custom texture loading logic so that D3D11, GL core (used on OS X) and GLES code paths have less broken custom textures.
Software renderer: Update a reference link.
Merge pull request #308 from neobrain/master

Software renderer: Update a reference link.
Merge pull request #307 from neobrain/custom_textures_workaround

Workaround dumb custom texture loading logic.
Add remaining possible uses of MOVBE

Also fixes a missing 'break' statement in DisassembleMov().
BackPatch: make sure MOVBE is long enough