Every municipal corporation in this State containing a population of at least 1,000 persons as shown by the last official federal decennial census may proceed as set forth in this chapter to amend its municipal charter and may, subject to the conditions and limitations imposed by this chapter, amend its charter so as to have and assume all powers which, under the Constitution of this State, it would be competent for the General Assembly to grant by specific enumeration and which are not denied by statute. This grant of power does not include the power to enact private or civil law governing civil relationships except as an incident to an exercise of an independent municipal power, nor does it include power to define and provide for the punishment of a felony.