fix unicode handling in iCalendar file generation.
fix unicode handling in iCalendar file generation.

closeio/nylas,closeio/nylas,nylas/sync-engine,closeio/nylas,jobscore/sync-engine,closeio/nylas,nylas/sync-engine,nylas/sync-engine,jobscore/sync-engine,nylas/sync-engine,jobscore/sync-engine,jobscore/sync-engine