Add missing dependency in Kraken exchange

Added 'moment' dependency. It is required for the retry method which
will crash without it.
Merge pull request #182 from iceydee/fix_kraken_retry

Add missing dependency in Kraken exchange
minimal order now differs per market, added kraken in docs
Merge branch 'localDB' of github.com:askmike/gekko into localDB
cleanup from debug
removed debugging amount from btc-e
fixed #184
added versioning
added version logging on db error
fixed #190
fixed #188