Amended suggestion description for ext-exif, removed exif as dependency for dev and removed mbstring entirely.
testSaveWithoutFormatShouldSaveInOriginalFormat will now be skipped if ext-exif isn't installed.
Apply an animation delay of 0 (which is perfectly valid) properly
Merge branch 'feature/animated-gifs' into develop

* feature/animated-gifs:
  Apply an animation delay of 0 (which is perfectly valid) properly
  testSaveWithoutFormatShouldSaveInOriginalFormat will now be skipped if ext-exif isn't installed.
  Amended suggestion description for ext-exif, removed exif as dependency for dev and removed mbstring entirely.