check for php 7.3

php 7.3.0 is released on dec-06-18.
http://php.net/ChangeLog-7.php#7.3.0

added badges for number of issue, release and license. It will give quick info to users about q2a project.

Add localization to plugins under qa-plugin

Added checkmark to admin labels

Turn all remaining AJAX calls in admin into JSON

Use JSON in admin_click AJAX calls

Allow closed and hidden questions to be deleted with one click

v1.8.1

nested list for RTL layout

Try to guess the appropriate protocol when generating the site URL

Fix many phpcs complaints

Add email field type to forms

Remove some deprecation messages

Avoid sending emails to blocked and unapproved users

Remove essential CKEditor configuration from config.js file

Add jquery and other dependencies before addon dependencies

Fixes #691

Added checkmarks to strings that are showing up in admin/stats after successfully finished progress. This helps a lot to better see a finished progress,