Removed `--initial-gas-price`, `--increase-gas-price-by` and `--increase-gas-price-every` args
Removed `--initial-gas-price`, `--increase-gas-price-by` and `--increase-gas-price-every` args

Not useful after the Byzantium fork.
The actual IncreasingGasPrice logic stays in place, so keepers can use
it by referencing that class directly.

makerdao/keeper,makerdao/maker.py,makerdao/keeper,makerdao/keeper