jbaik OBV Total for BTC

Simply added all obv for BTC from different tickers

Tickers included :

BITMEX:XBTUSD
BITFINEX:BTCUSD
COINBASE:BTCUSD
BITSTAMP:BTCUSD
KRAKEN:XBTUSD
HITBTC:BTCUSD
CEXIO:BTCUSD
BINANCE:BTCUSDT
BITTREX:BTCUSDT
BITFLYER:BTCJPY
BITHUMB:BTCKRW
KORBIT:BTCKRW
KRAKEN:XBTEUR
BITFINEX:BTCEUR
BITSTAMP:BTCEUR
COINBASE:BTCEUR
BINANCE:BTCUSDTPERP
BYBIT:BTCUSD
OKEX:BTCUSDT