Add logging

[TuringTux]

Currently, the plugin comes with very little logging, I believe.

It would be great if the plugin included logging (especially error logging), so that in case of problems debugging is easier.

The first step (for me, at least) would be to find out how logging is handled in Taiga, so that the plugin can output the logs to the same place where Taiga is storing them, so that they are all in one place.