Fix activeOwnersCount initialization in MultiSigGeneric

[0xNeshi]

Ticket(s): #199

Explanation of the solution

Variable activeOwnersCount should be initialized in MultiSigGeneric.initialize otherwise it always remains 0 (zero), causing unintended behavior later on (e.g. when adding/removing owners -> if we try to remove an owner, activeOwnersCount would be set to a negative value which is impossible with it being a uint256, causing a revert to happen).

It was necessary to redeploy CharityApplications and APTeamMultiSig proxies as well because their initialize methods had to be called again.

Instructions on making this work

• run yarn or yarn install to install npm dependencies
• run yarn test to verify all tests still pass
• read activeOwnersCount for any of the multisig contracts
• verify the actual value is the expected one (the "real" number of owners passed in initialize function)