chore: move encrypted tokens to environment variables

Author: eshanholtz

.travis.yml

@@ -20,5 +20,4 @@ notifications:
  on_pull_requests: false
  on_success: never
  on_failure: change
- rooms:
- - secure: OMxOft/oHZcNVog6KItt3/+y8lux+PMUPaAUBRlDV6csQ6QcUvMtpml8PBh+Z/0wzkIBayZG4XCKlSXnOf1yVvlNE+NWNGmG8ClRYjS2qTJcH1VnWwIxWB/TUKnXxOQar5db04RwH6qtAOv72JfI7c5LI/KlI8MEK0cy1JsI4Yc=
+ rooms: $SLACK_TOKEN