Added list of valid audio and video file extentions.

Added getFormat method. Added code for getAudioSampleRate, getAudioChannels,getAudioBitDepth, getVideoCodec, getVideoFrameRate, getVideoBitRate, videoBitRateH, videoResolution, videoResolutionHeight, videoResolutionWidth, fileSize, fileSizeH

Fixed getMD5 and getSHA1 so they are producing the correct hash values.