Do not use minimetoken as standard

[leekt]

There is a possibility of Overflow on totalsupply and balance when using generateTokens(), doTransfer(),
Also Reentrancy Attack is easily done by Controller.

issue stated on Giveth/minime#60

[clesaege]

• Only problematic for tokens having more than 2^128 - 1 token units.
• The controller is a trusted contract, if it were to be compromised there is way better way to exploit it than try to reentry.