Make some tx_pool methods private
Make some tx_pool methods static
Use const where appropriate in tx_pool
Add transaction size limit

Transactions larger than the limit will not enter the pool
Start fresh if tx_pool deserialize fails
Minimum tx fee for entering pool
Use print_money in log
Decrease max block size from 200% median to 130%
Don't check for min fee when adding tx to block

This is now done when transactions enter the pool.
Don't check max tx size when adding to block

This is now done when adding transactions to the pool.
Remove second tx size check
Remove dead code
Merge pull request #64 from mikezackles/bytecoin_tx_pool_tmp

tx pool fixes, courtesy of Bytecoin