Implemented sf.SoundRecorder select device API

New in SFML 2.2.
Updated sf.SoundRecorder.start() to refelect the new API

s::SoundRecorder::start() returns a boolean in SFML 2.2.
Added sf.Text.STRIKE_THROUGH

New in SFML 2.2.
Implemented sf.Touch API

New in SFML 2.2.
Implemented sf.Sensor API

New in SFML 2.2.
Implemented sf.Keyboard.set_virtual_keyboard_visible()

New in SFML 2.2.
Implemented sf.Touch and sf.Sensor events

New in SFML 2.2.
Implemented request focus API

New in SFML 2.2.
Fixed sf.Sensor.SENSOR_COUNT

To be consistent with KEY_COUNT, JOYSTICK_COUNT, AXIS_COUNT, etc.