* removing duplicate translation key
* fixing typos
* extracting quest prerequisite check. adding check for previous quest completion, if required
* fixing (undoing) static change, adding tests
* more typos
* correcting test failures
* honoring quest prerequisites in quest invite API call. updating format of il8n string replacement arg
* no longer using apiError, use translate method instead (msg key was not defined)
* adding @apiError to docblock as requested in issue
* removing checks on quest invite method. small window of opportunity/low risk