Fix split threshold

- Can phai chuyen anh sang anh gray truoc khi tien hanh tach nguong
 On branch SplitThreshold
	modified:   RecognitionFingerprint/src/com/vnexit/fingerprint/datamodel/SplitThreshold.java
	modified:   RecognitionFingerprint/src/com/vnexit/fingerprint/form/Fom.java
	modified:   RecognitionFingerprint/src/com/vnexit/fingerprint/gaborfilter/GaborFilter.java