Tell CMake to install the compiled binaries on Linux.

Add GL_CLAMP_TO_BORDER support.

Travis: Remove use of sudo to enable use container-based builds

Update style rules with to better match current practice.

CMake: Fix Debug build configuration in MSVC

Common: Remove thunk.h

This isn't used, and there's no implementations of the member functions.

Cleanup includes, mostly in common

This will help packaging tremendously, as a `make DESTDIR=… install` will now
put every file at their place (on Linux and related).

Debug was missing compiler flags, causing MSVC to default it to building
with optimizations enabled (making for a not very useful binary for
actual debugging...). Additionally, the variables were re-organized to
remove some redundancy, the old Release build type was removed, and
RelWithDebInfo was renamed to take its place instead.

Loader: Fix format specifier warning

AppVeyor: Remove submodule checkout depth

This avoid intermittent build failures due to a commit not being
reachable using a fixed depth, at the expense of longer checkout times.

Implement blended downscaling for display transfers

Services/SOC: Added command headers to some of the soc commands.

vfp: Change return type of VFPInit from unsigned int to void.

vfp: Handle accesses to FPINST/FPINST2 system registers.

Also has a side-benefit of correcting access to the FPEXC register.

Remove unused type unions breaking aliasing rules in horrible ways