Min OSX SDK 10.9
Let CaptureSession::setDevice() check if device is initialized and
ready before proceeding. Also it will stop if session is running and
it will clean up any existing input device, if present.
If a previous output device is present when asking for snaptops then
destroy it and recreate.
Reuse the output device handle as much as possible and cleanup
everything (except the session) when setting a new device.
Check if snapshot actually succeeded.
Added deps on Qt5 and auto Moc'ing.
Removed debug info.
Updated readme.
Using QString and QDebug.
Removed obsolete toString() method.
Changed from std::vector to QList and using a foreach construct.
Reserve list length because it is known.
Using QImage for images.
Changed readme.
Simplified arguments parsing.
The extension of the output filename dictates the output format (jpg,
jpeg, and png allowed now).
Updated readme with usage of snapshot.
Implemented --quality|-q <n> option for setting 1-100% quality.
Implemented --scale | -s <res> that enables the user to scale to a
fixed WxH or to a certain width or height individually.
Updated readme and gitignore.