[+DS] Interim Change

In progress. Missing updating tests.
Finish tests; support for custom empty messages; classes separated to different files
Update documentation
Remove unnecessary indentation in README
Include all test files
[+DS] Make test running together
Fix link
[+DS] Make Travis happy
Merge branch 'seo_sort_by_and_filtering' of https://github.com/reevoo/reevoomark-php-api into seo_sort_by_and_filtering
[+DS] One more chance of Travis
[+DS] Fix text on travis
[+DS] Another try for Travis
[+DS] Fix for travis.
[+DS] Fix travis.
Try and fix travis
Try and fix travis
Changes after code review

Changes after code review
Merge pull request #6 from reevoo/seo_sort_by_and_filtering

PHP API v2