remove unnecessary imports
fixed the problem with the ivffile protocol being unknown by JMF.
It was in fact known by it, but the constructor of the DataSource was calling
the function "getCaptureDeviceInfo().getLocator()" or just "getLocator()", but
the MediaLocator and the CaptureDeviceInfo are not known during the constructor.
->Move the code to the function "doConnect" that is called after the MediaLocator
is set.