Overloaded calMD5Value method

[git-p4: depot-paths = "//xFace-Apollo/branches/openxface-android/": change = 17381]
Deleted apollo certificate

[git-p4: depot-paths = "//xFace-Apollo/branches/openxface-android/": change = 17382]
Optimized XAssetsFileUtils

[git-p4: depot-paths = "//xFace-Apollo/branches/openxface-android/": change = 17383]