Apply fixes from StyleCI

Merge pull request #90 from rez0sk/master

Upgrading Corcel to match Laravel 7 requirements

Merge pull request #83 from corcel/develop

Update to Corcel 3.0

Merge pull request #76 from corcel/develop

Release last changes on develop branch

Merge pull request #56 from omzy83/ACF-50

maintain image order

Update composer for php>=55

- Fix posts order.

- Bugfixes

- Fix URL bug in Image field;

- Add option to get the default WP behavior when getting images sizes;
- Add new tests for the Image field.