Added tests of sasl utils
Fixes of bugs in sasl utils founded by tests
Extended tests of StringPrep and HexConverter
Fixed directionality of chars in StringPrep
Extended utils tests + codestyle
Fixed StringPrepTest (by ELY-47)
Follow up code clean up: -
 - Removal of tabs for indentation.
 - Added license headers to new classes.
 - Added @Ignore to a set of tests currently failing.