add unit tests (issue #7)

This version introduces multiple enhancements:

added some other methods tests
fixed some tests
fixed remove errors and unserialize method

Details of additions/deletions below:
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Modified:   Base/BlueObject.php
            -- Updated --
                unserialize use appendSerialize instead of constructor call
                removeObjectError set _hasErrors to false

Modified:   Test/ObjectTest.php
            -- Updated --
                testSetDataInObjectByDataMethod removed deprecated method setData, ad replaced by appendData
                testAccessForNonExistingMethods added also check removing object errors
                testCreationWithSerializedObjectDataPreparation replaced appendSerialize by unserialize