Added onboarding tooltip for edit button
Merge branch 'develop' of github.com:wordpress-mobile/WordPress-iOS into feature/editor-165-onboarding

# By Matt Bumgardner (1) and Sendhil Panchadsaram (1)
# Via Sendhil Panchadsaram (2) and others
* 'develop' of github.com:wordpress-mobile/WordPress-iOS:
  Giving a shell script better name
  Updated x and chevron icon
Now shows the onboarding hint the first time through only
Added a 0.5 sec delay before displaying tooltip
Updated constant name
Merge pull request #2927 from wordpress-mobile/feature/editor-165-onboarding

Onboarding tooltip for new editor