Added Matrix3[d].Add and Matrix4[d].CreateFromRotationMatrix
Changed Matrix4[d].CreateFromRotationMatrix to a new constructor.
[Input] Add GamePadCapabilities.IsMapped
[SDL] Correctly byteswap Guid

Fixes an issue where GamePad Guids would fail to be matched with the
Guids in the configuration database.
[Input] Fixed bitwise test for GamePadAxes
Merge pull request #176 from Robmaister/develop

Added Matrix3[d].Add and Matrix4[d].CreateFromRotationMatrix
[Win] Suppressed spurious warning
[Win] Fixed XInput y-axis and trigger range
[Win] Removed unused code
[Input] Special-case pre-SDL2.0.4 xinput bindings

Starting with SDL 2.0.4, its xinput bindings are working correctly.
Previous versions would return an invalid zero guid and use incorrect
mapping - this has now been fixed.
Merge pull request #161 from thefiddler/win_xinput

[Win] HID-based IJoystickDriver2; improve XInput2 IGamePadDriver
[Mac] Fixed joystick Guid calculation

The result now matches the output of SDL2 as well as the entries in the
GamePad configuration database.
[Mac] Use cookies to match HID joystick elements
[Mac] Added CFGetTypeID method
[Mac] Sort joystick elements like SDL2

GamePad configuration database is now working correctly on Mac.
[Mac] Fixed Joystick Hat calculations
[Mac] Match SDL2 element order

Joystick elements (axes, buttons, hats) are now reported in the same
order as SDL2. This fixes potential mismatches in the GamePad
configuration database.

Additionally, elements are now counted correctly (duplicate elements no
longer count towards the total.)
[Input] Added From* overloads with out parameters
[Mac] Use DeviceCollection

This reduces code duplication significantly.