Merge pull request #636 from zholmes1/develop

[BITTREX] User trade history
Updated with current symbol pairs

Added missing symbol pairs, removed old GHS NMC pair. (gives an error now)
Merge pull request #637 from Achterhoeker/patch-12

Updated cexIO with current symbol pairs
added timestamp to Bitfinex orderbook
added timestamp to Kraken orderbook
added timestamp to VoS orderbook
fix for previous updates with bug
Merge pull request #1 from timmolter/develop

Update