begin()
initialise bus i2c. Initialise sensor. Checks chip id. ccs.begin(addr, wire, scl, sda)ccs: a variable of type ZUNO_CCS811.
addr: bus sensor address i2c CCS811_ADDRESS(0x5A) and CCS811_ADDRESS2(0x5B) - default CCS811_ADDRESS.
wire: object pointer Wire - default Wire.
scl: pin SCL - default SCL(9).
sda: pin SDA - default SDA(10).
bool - true on success, false otherwise