Woocommerce Sensei LMS 2.4.0

* Fix Add learner to course and complete course sends two duplicate emails
* Fix Modules: WooCommerce 2.6.x Select2 compatibility fix
* Fix Incorrect heading structure: Use proper headings hierarchy for settings and data updates
* Fix Usernames with a . or @ don't work for loading user profiles (Get learner profiles by login, not slug)
* Fix Fatal Jetpack removing module taxonomy
* Add bulk recalculate completion
* Fix Modules: Teachers should only view their own modules
* Fix: Lesson image does not display on single course page [Pri] Low [Type] Bug
* Add User Courses Shortcode: Filter for conditionally displaying toggles
* Fix Memberships: Query all restricted content
* Fix Lesson image does not respect size setting
* Fix Remove trailing whitespaces from translatable strings [Pri] Low [Type] Bug
* Fix Unable to add Existing Questions to Quiz with Search Filter (PHP 7.1.4)

* Fix - Prevent multiple emails being sent to learners already started on a course.
* Fix - Course content disappears
* Fix - Prevent certain scenarios where course start date was resetting when visiting my-courses
* Fix - Don't send confusing registration emails to users
* Fix - Learner Profile White screen
* Fix - Prevent users from buying duplicate courses
* Admins can now edit learner course start dates

* Improve handling of get_bloginfo( ‘admin_email’ ) #1809
* Fix With [sensei_courses] short code on product page, up-sells disappear #1800
* Fix Users not being added to purchased courses again #1808 1810
* Fix Select2 (Can’t add course when editing Module)
* Better 2017 Theme Support
* Even Better Memberships Integration
* Other small bugfixes and improvements