Added a test case to method getPOSptn(). Fixed a bug of it.
Added a new class StringAndInt to represent the return value of doIt() method in ruleBasedLearn().
Added methods equals() and hasCode() to StringAndInt class. Added a test case of case 1 to method doItHelper().
Added a new class, IsAValue, to represent the value of an entry of the isA table.
Added a add2IsAHolder() method to DataHolder class. Added case 3.1 of method doItHelper() method. Have not tested yet.