Adding togglable ANSI colored logs

[Vicepredator]

This is a fork of @xHeler 's idea of implementing ANSI colours to distinguish different log types.

I have added the possibility to enable/disable (default disabled) this functionality either from the constructor:

Log.begin(level, &Serial, showLevel, showColors);

or by calling the specific method:

Log.setShowColors(showColors);

I also improved the readability of the code by refactoring the part that deals with printing ANSI codes

[Vicepredator]

Maybe in the future I will add full customization of the colors...we will see. By the way, this PR is already a great improvement for those like me who use ANSI serial monitor

[vzahradnik]

Since this repository seems unmaintained, I decided to grab all pull requests in this repo which seemed polished enough and I added my own changes. I plan to maintain my fork and I'm sharing the link here just in case it would be useful to someone else. The library is already published in the PlatformIO registry.

Check the release page for full details.

Pull requests are welcome :)