Character details improvement

In module character details, to get name of an unicode character, UnicodeData.txt(1.5 mb) was being parsed each time as Character.getName(int) was included only in API level 19 (http://developer.android.com/reference/java/lang/Character.html#getName(int) ) and could not set minsdk to 19. So I extracted the implementation of that function from java open source and applied it here and it seems to have way better performance. Thank you