added to DCharacterGRC.get_sourcestr_representation() the 'ignore_makron' parameter
added new function DStringGRC.get_sourcestr_representation() overloading DString.get_sourcestr_representation() to take the 'ignore_markron' parameter in account
added a new test : TESTSDStringGRC.test_get_sourcestr_repr3, testing the 'ignore_makron' parameter.