Report the message levels on the human logger

[matteosuppo]

Signed-off-by: Matteo Suppo [email protected]

[coveralls]

Coverage remained the same at 57.014% when pulling 2dee1c3 on humanlevels into bc2c38f on master.

[matthijskooijman]

Code looks good. What's the intended usecase for this logger?

[matteosuppo]

On create we use the human logger, but we would like to use different colors for the different levels.

This way we could also identify what's the issue in this case, for example:

human

Global variables use 3009 bytes (146%) of dynamic memory, leaving -961 bytes for local variables. Maximum is 2048 bytes.
Not enough memory; see http://www.arduino.cc/en/Guide/Troubleshooting#size for tips on reducing your footprint.

humantags

[info] Global variables use 3009 bytes (146%) of dynamic memory, leaving -961 bytes for local variables. Maximum is 2048 bytes.
[error] Not enough memory; see http://www.arduino.cc/en/Guide/Troubleshooting#size for tips on reducing your footprint.```