Handle 'Unexpected IDLE response' errors in IMAP polling.
Handle 'Unexpected IDLE response' errors in IMAP polling.

nylas/sync-engine,ErinCall/sync-engine,nylas/sync-engine,gale320/sync-engine,closeio/nylas,ErinCall/sync-engine,closeio/nylas,gale320/sync-engine,nylas/sync-engine,gale320/sync-engine,ErinCall/sync-engine,Eagles2F/sync-engine,ErinCall/sync-engine,jobscore/sync-engine,gale320/sync-engine,closeio/nylas,Eagles2F/sync-engine,jobscore/sync-engine,gale320/sync-engine,Eagles2F/sync-engine,closeio/nylas,Eagles2F/sync-engine,nylas/sync-engine,jobscore/sync-engine,ErinCall/sync-engine,Eagles2F/sync-engine,jobscore/sync-engine