[#15003063] removing Finished contribution event from mixpanel
Merge branch 'master' of github.com:catarse/catarse into mixpanel_tweaks
[#15003204] adding Engaged with Catarse mixpanel event to the contribution confirmtion
[#15003204] added events as Engaged with Catarse to mixpanel tracker. Changed some old ones and added new events as well.
Merge pull request #957 from diogob/mixpanel_tweaks

Mixpanel tweaks