Market: add kraken for ticker and depth
Market: depth queries now support multiple currencies.
Market: add bitmynt.no ticker
Market: add bitcoin-central for ticker and depth queries
Market: add bcent to ticker all market summary
Market: add bitcoin-central vwap to ticker output

they just added vwap to their ticker api.
Merge branch 'master' into dev

Conflicts:
	Market/plugin.py