Originally I changed the compiled output of TinyMCE from es2015 to es6
to try and allow our own requirejs system to serve the content.
This is a change in the TinyMCE repository (or our copy of it).
Unfortunately this turned out to not be possible, but I never got around
to updating the configuration to stop doing so.
Whilst working on this issue, I've removed this change to module
compilation, which brings us closer in line to Tiny core, and simplifies
the upgrade process.
Part of MDL-75966
This commit adds TinyMCE version 6.1 into Moodle core.
A basic editor implementation is included, along with Moodle loader, and
basic Plugin API for Moodle. The Plugin API will be extended and
improved in future changes.
A new subplugin is defined for this plugin.