Switch to polling setup

[bschulz1701]

Feature:

Change from using fixed delays to using Active Force Mode (see COMMAND register) and polling the device for new data.

Make a function getNewData() which will call for a new data reading, then block until done. Function will return I2C error code normally or -1 if function timed out.

Check documentation if there is a better number, but 1000ms should be plenty for a timeout given the longest reading period is 400ms