fetchTicker for a particular day

[treygriffith]

On the broker, the getMarketStats method will only return the last 24 hours of data to the user.

We are currently missing the following open/close pricing because we do not allow the user to specify a datetime for the price ticket (we only return the previous 24 hours)

• open (opening price, 00:01 of day)
• close (closing price, 23:59 of day)
• last (same as close, but both terms are used)
• previousClose (closing price of previous day)
• change (last - open)
• percentage (change/open * 100)
• average (last + open / 2)

Tasks:

• Add a date param to getMarketStats to allow for historical data (this might be another call in CCXT)