[4.1-beta][Feature] A different field for editing markdown, retire SimpleMDE

[tabacitu]

SimpleMDE has not received an update in 4 years, and recently I've started receiving security alerts about it. Nothing we should worry about yet, but considering it's abandoned, we can be pretty sure that when a big problem will be discovered, it won't be fixed.

We should retire simplemde in favour of some other editor for markdown. I've done a little research and found:

• tui editor - seems to look & work great;
• editor.md - seems a bit targeted at Chinese developers; we should double-check if the documentation is all in English and everything's ok;

If anybody knows of a better Markdown WYSIWYG editor - please let me know.

[ziming]

The thing i like about simplemde is how it doesn't assume user know how to bold text or do bullet points through shortcut keys and provide icons to click for them. Hopefully the replaced markdown editor do that too.

Nova chosen markdown editor library didn't come with icons for unordered or ordered list for example. And my observation from users who aren't familar with markdown is they try to copy the bullet point circle from microsoft word and paste it in the markdown editor instead. :(

An example of how things could go wrong if there isn't enough formatting icons in the markdown editor

[tabacitu]

EasyMDE seems to be a very well-maintained fork of SimpleMDE. Might be best to use this one.

[tabacitu]

Fixed by https://github.com/Laravel-Backpack/CRUD/pull/2737