Coin Magi (xmg) Release m-wallet-v1.4.4.1

This release solves the recent blockchain forking issue, including the follow changes:

Synchronizing checkpoint & master server introduced; this is to remove constantly checking on the misbehaving and IP banning, along with the error "block with too little proof-of-stake or proof-of-work". The checkpoint master server and keys remain to be used from now on; they are likely to be removed in the future;

Implemented a block generation rule: PoW / PoS blocks are mined / minted by following a pattern: 1) at least two PoS blocks minted between two consecutive PoW blocks, or PoW blocks generated every 10 minutes; 2) at least one PoW block is found in five consecutive PoS blocks, or PoS blocks generated every 3 minutes;

Difficulty adjustment will be changed to four-block exponential moving average. When there is violation in aforementioned PoW / PoS generation rule, the difficulty remains unchanged.

The following hard forks are scheduled to implement the changes:

block 1481500: PoW / PoS block generation rule, and also exit point of the maintenance mode;block 1482000: difficulty adjustment algorithm switch.