improve summernote of the composer

[fabienmoyon]

Current

We are currently using the fork version v0.8.2-1 released on 21 Sep 2016 linagora/[email protected] (release) and OpenPaaS-Suite/esn-frontend-common-libs@main/package.json#L72

Expected

Upgrade to last version (currently the v.8.20) https://github.com/summernote/summernote/releases/tag/v0.8.20

With this last version, we will be able to fix some issues like #427 and also will fix many issues met by users.

Tests cases

After the upgrade we need to test many cases to be sure the last version expect that we currently have on the composer.

1. Be able to undo by shortcut ctrl + Z
2. Be able to copy paste images, sentences, files
3. Be able to drag and drop images, sentences, files
4. Copy paste a sentence must be exactly the same result from the source file and from different sources (gmail, obm, LibreOffice, onlyoffice, pad ...) :
   • Links and hyperlinks must be present
   • Bold, Italic and underline must be also the same
   • Background Color, Foreground Color also
   • Paragraph Align and justification also
   • Outdent and indent also
   • Unordered list and ordered list also
   • Line height must be the same
   • Spaces between sentences also

[alagane]

Cannot use v0.8.20 because of a bug fixed but not yet released: summernote/summernote#4164
But v0.8.18 is ok and fixes #515

[alagane]

Here is the report of tests with screenshots, against some mail web client, and summernote demo (on official website), all on Firefox
Sources are LibreOffice composer_test_page.odt and Google Document doc
summernote_tests.pdf

Also the new "link edit" feature of summernote seems a little bugged on Inbox:

It looks like this on summernote demo:

[alagane]

I Just noticed the demo on summernote.org is not 0.8.20 but 0.8.18, so the same version we will be using.