ValueFormatter getFormattedValue needs also function with Double

[Paget96]

Here is whole issue which exists since long ago
PhilJay#2891

Also would be nice if we can map formatter with Entry data where we can pass multiple info regarding the Entry.

This is needed when we want to add Unix timestamp to X axis. if we do add it now and convert to float, precision is lost, and line is going everywhere but not where it supposed to go.

[hannesa2]

Isn't it enough to simple convert double to a float ?
https://github.com/AppDevNext/AndroidChart/pull/223/files