During the last meeting, some problems were pointed out.
This commit should fix some of them.

After the marks have been added,
the only thing missing is Katex.
Katex must be implemented in a different way,
because the html data has to be enclosed
by a Quill container.

A partial commit to the upcoming meeting.

[Ticket: #219]

[Ticket: #210]

fix ui for spellcheck error.

This reverts merge request !29

This reverts merge request !24

parse Language Tool API response,
mark all wrong words,
adding a button which activates grammar checking.

Lukas Haase authored 4 years ago and Tom Käsler committed 4 years ago

i18n support, remove comments

Add select menu on creating a comment
Add small section in comment mat card for displaying the comments