Merge pull request #36 from chajr/fix

set data with check (issue #11)
hasData error (issue #39)

This version introduces multiple enhancements:

replaced all isset functions by array_key_exists to solve error with null value
also some small refactor

Details of additions/deletions below:
--------------------------------------------------------------

Modified:   Base/BlueObject.php
            -- Updated --
                __construct isset rteplaced by array_key_exists
                __call isset rteplaced by array_key_exists
                getData isset rteplaced by array_key_exists
                returnOriginalData isset rteplaced by array_key_exists
                hasData isset rteplaced by array_key_exists
                compareData isset rteplaced by array_key_exists
                unsetData isset rteplaced by array_key_exists
                restoreData isset rteplaced by array_key_exists
                _putData code convention fix and give value of hasData to _changeData
                _changeData isset rteplaced by array_key_exists annd added $hasData variable to stop execution of hasData inside of method
                _convertKeyNames isset rteplaced by array_key_exists
                _arrayToXml isset rteplaced by array_key_exists
                _convertArrayDataToXml isset rteplaced by array_key_exists