system contract undelegatebw bugfix: don't delete row if ram_bytes != 0, small change in resource_limits to make debuging less confusing #3366

This reverts commit 3b5e03df.

- all ram trading fees sent from user to eosio.ramfee (also implement 1% fee Fix #3182)
- all tokens received for ram sent to eosio.ram
- all proceeds from selling ram sent from eosio.ram
- all staked tokens sent to eosio.stake
- all unstaked tokens sent from eosio.stake
- fix build dependency issue with ram_tests

cancel_deferred returns 0 (transaction not found) or 1 (canceled), don't reset refund timer when taking moner from refund to stake #3180

- also exempt the eosio account from this restriction

- fix warnings in eosiolib
- remove debug print statements from contracts
- erase the delegate_bw object (didn't actually remove voter info
                                object)
- remove user balance object from token contract when balance goes to 0

- don't store balances in ram as asset
- refactor producer pay algo to not iterate over all producers
- perform one percentage-based calculation
- partially fix unit tests
- use higher precision time

Added a unit test that would buy/sell a small amount of RAM and a large
amount of RAM.  This test showed unexpected behavior due to attempting
to sell over 2^32 RAM.  I updated the sellram action to enable selling
more than 2^32 bytes at once.

Test results show that for both large and small quantities, the user
losses a small amount of tokens and does not profit.

(cherry picked from commit 10273fa2d180f81769516b507bfdff68f06b7f87)

- update system contract with setram that properly updates market
pricing

1. transfers are now prevented where from/to are same
2. inline transfers to self are now skipped (eosio staking for others)
3. unit test updated to demonstrate staking works