Add TinyMCE 6 module

[renoth]

There are serious security issues with TinyMCE 4 and 5 https://security.snyk.io/package/npm/tinymce

Furthermore TinyMCE 4 is not updated in wicketstuff tinymce 4 and still on version 4.3.4, see also https://security.snyk.io/package/npm/tinymce/4.3.5

The migration to TinyMCE 6 should be straightforward but there are some plugins which have become usable only with subscription. This implementation only supports the free part of TinyMCE 6 retrieved from here https://www.tiny.cloud/get-tiny/self-hosted/

If you like the changes, please do a codereview (and maybe merge later). Thank you for your time.

[renoth]

I also removed the ImageUploadHelper et al and JazzySpellChecker (is now done directly via browser API) and the InPlaceEditComponent.

[martin-g]

Thank you, @renoth !

[solomax]

@renoth shall we drop tinymce3-parent and tinymce4-parent ?

[martin-g]

@renoth shall we drop tinymce3-parent and tinymce4-parent ?

+1

[renoth]

I would update tinymce4 to the latest version of TinyMCE 4 since it works just fine. This module does have some features removed compared to TinyMCE4. TinyMCE3 can be removed imho

[renoth]

Looking at the vulnerabilities again, i think it is time to drop TinyMCE 4 as well

[solomax]

Many thanks! Dropping 3 and 4 for master branch :)