Change 'monetory' to 'paid'

Created by: wmortada

Thanks for developing a great extension! I have a minor suggestion to improve the language used in one of the reports.

The events visualisation report contains a graph titled: 'Is Monetory?' This is spelled incorrectly. It should be 'monetary' rather than 'monetory'. But rather than just correct the spelling, I would suggest that it would be better to change the title to 'Paid event' and change the other occurrences of 'monetory' to 'paid' throughout this report. I think that is simpler and clearer language.