Update Utils.java

[Sublimis]

Use double-s instead of float-s to minimize rounding errors that can lead to axis labels saying e.g. "9999.999" instead of "10000". There's really no excuse for using float-s here, and probably throughout much of the rest of the code, too. Maybe this remark could be taken into consideration to prevent similar problems in the future.

[Paget96]

I really like this library and using it in my apps, I would like to call people to continue with this awesome thing. I have forked the repo and started working on it! So I am ready as well to accept pull requests, I'll notify other people from here as well! Would be more than happy if we continue with this awesome project.

Code is full kotlin now!

Make your pull requests here: https://github.com/Paget96/MPAndroidChart