Changed methods around to make it more of a 1 to 1 replacement for ofVideoPlayer
Added volume control to video player

This commit implements volume control for the video player. One should
be extra careful and test edge cases (ie setting sound when opening a
file, closing, ...)
Added function to query frame rate of a loaded video

The user can now query the frame rate of a loaded video. The value is
stored in a local variable which is being reset every time a new movie
is loaded.
adding methods to implment ofBaseVideoPlayer
Merge branch 'master' of github.com:secondstory/ofxWMFVideoPlayer into ofbasevideoplayer
Merge remote-tracking branch 'igierard/ofbasevideoplayer'

Conflicts:
	src/ofxWMFVideoPlayer.h
set normalized position
RefCounterObject is RefCounterObject_ as an ugly patch to overcome ambiguity with Poco::RefCounterObject