4.1.0-beta1

Added

• Implement a new compliance module Supply Limit Module that prevents minting more tokens that the specified limit.
• Implement a new compliance module Time Transfers limits that prevents holders from transfering more token than a specified limit in a given time frame.
• Implement a new compliance module Max Balance Module that prevents an individual holder to own more than a given percentage of the supply.
• Implement two new compliance modules Time Exchange limits and Monthly Exchange limits that limit exchanges transfers. These are used to authorized specific trusted exchanges to hold tokens but limited to a certain amount transfered for a given time frame.
• Add function name() external pure returns (string memory _name); to IModule. Compliance modules now require a
  function name() public pure returns (string memory _name) { return "CountryRestrictModule"; }
  constant variable to be declared.
• DVATransferManager contract