PHP client implementation for aNewSpring API

This PHP client makes it possible to manage users, user groups, single sign-on (sso) access codes, courses, course subscriptions and instance management.

For more info see: https://support.anewspring.com/en/articles/70410-api-introduction

It is not possible to use the aNewSpring API to:

1. delete a role: deleteUserRoles
2. see which groups a user is a member of: getUser => groups
3. request information from a group: getGroup and getGroups
4. quickly update all facilitator/participant relationships: getTeacherStudents
5. request permissions of a course: getCoursePermissions