Fixed#135: Change services service priorities
Fixed#136: ErrorManager: Implement recognize_error
Fixed#137: BNFNodeParser : Error when parsing regex with sub parsers
Fixed#138: get_last_errors(): real errors sources are lost
Fixed#139: OneError return value removes the origin of the error
Fixed#140: Concept variables are not correctly handled when parsing sub expression
Fixed#143: Implement has_unknown_concepts()
