Introduced precision params for other endpoints

The uses of 'precision' parameter allows to specify price data in full or 0-18 decimals, and previously was only made available for /simple/price and /simple/token_price/{id} endpoints.

This parameter is now supported for more endpoints as listed below:

• /coins/markets
• /coins/market_chart
• /coins/{id}market_chart/range
• /coins/{id}/contract/{contract_address}/market_chart
• /coins/{id}/contract/{contract_address}/market_chart/range
• /coins/{id}/ohlc