AVIDump: cleanup
AVIDump: update ffmpeg/libav API usage

libav 10 was released on May 10th, 2014 and it drops support for some
long-deprecated stuff like avcodec_encode_video().
CMake: remove unused/duplicate definitions
CMake: mention ffmpeg in libav messages

We support both.
CMake: update min. libav/ffmpeg library versions
AVIDump: rename frame variables
enum CPUState: rename CPU_* to STATE_*
CoreParameter: add enum CPUBackend
Don't install segfault handler in interpreter mode
Merge pull request #328 from Tilka/enum_cpubackend

Don't add segfault handler in interpreter mode
Merge pull request #362 from Tilka/ffmpeg_libav_new

AVIDump: use new ffmpeg/libav API
VideoCommon: Get rid of an snprintf call in VideoConfig.cpp
Merge pull request #571 from lioncash/snprintf

VideoCommon: Get rid of an snprintf call in VideoConfig.cpp
Introduce the revised coding style.
Merge pull request #410 from lioncash/coding-style

Introduce the revised coding style.
Revert "Don't add segfault handler in interpreter mode"
Merge pull request #574 from dolphin-emu/revert-328-enum_cpubackend

Revert "Don't add segfault handler in interpreter mode"
D3D: Use std::strings for Compile[x]Shader and CompileAndCreate[x]Shader

With strings, we don't need to care about passing in a length, since it internally stores it. So now, we don't even need a length parameter for these functions anymore as well.
This also kills off some sprintf_s calls.
Merge pull request #576 from lioncash/shader-string

D3D: Use std::strings for Compile[x]Shader and CompileAndCreate[x]Shader
DolphinWX: Remove a wx  2.9.0 and 2.8.0 version check in GameListCtrl