The general grant of municipal power under this subpart is intended to confer the greatest power of self government consistent with the Constitution of Pennsylvania and with the provisions of and the limitations prescribed by this subpart. Any specific enumeration of municipal powers contained in this subpart or in other statutes does not limit the general description of power contained in this subpart. Any specifically enumerated municipal powers are in addition and supplementary to the powers conferred in general terms by this subchapter. All grants of municipal power to municipalities governed by an optional plan under this subpart, whether in the form of specific enumeration or general terms, shall be liberally construed in favor of the municipality.