Modified the additional current the iPad should draw

Changed the additional current the iPad should draw to match the MFi spec of 2.1 amps, rather than 26 amps previously. Our hardware was tripping a limit and shutting off the power because the iPad Air was drawing more than 2.1 amps.
Merge pull request #32 from chaosaddict/master

Changed the additional current the iPad should draw to match the MFi spec of 2.1 amps, rather than 26 amps previously. Our hardware was tripping a limit and shutting off the power because the iPad Air was drawing more than 2.1 amps - by https://github.com/chaosaddict. 

- Thanks chaosaddict