Discord, Plotsquard, Duels competitions

This update adds trackers for a duels event and plotsquared building competition in addition to integrating discord webhooks for periodic updates on the event progress. The duels webhook doesn't work.

Skipping 0.0.7 and 0.0.8 as they correspond to unpublished step-by-steps adding duels and plotsquared separately.

Also at some point global essentials nickname passing was added (in 0.0.8?).