Merge pull request #108 from DataDog/isaac/bug_fixes

Isaac/bug fixes
Merge pull request #109 from DataDog/isaac/bug_fixes

Isaac/bug fixes
Merge pull request #110 from DataDog/isaac/bug_fixes

Move Pillow to tests requirements
update readme api link [ci skip]

Fixes #111
Merge branch 'isaac/bug_fixes'
Merge last 3 versions together as they were
not released to pypi.
Refactor snapshot ready method to return the status code + update tests
Make snapshot path part of the url and improve tests