fix(zoom): Only set zoom to valid numeric values

bump(changelog): New features / fixes in 0.3.36

bump(version): 0.3.32

perf(travis): Fewer mac builds—Travis has fixed OS X bandwidth

fix(event-rsvp): fix issue with event RSVPs being repeatedly resent

Event RSVPs would resend every time the app was opened, due to `resolve`
never being called on the `Promise` after successfully sending an event
RSVP.

feat(rsvp): "Quick RSVP" to events recongized by the API

rm(spectron): Don't run during CI builds, it's timeout-based and fail…

…s randomly

fix(bootstrap): Set apm environment vars to avoid Atom conflicts