Add plugin dependencies documentation

[ptuytsch]

No description provided.

[hendrikVandeput]

I think it might be better to implement a markdown file per plugin in each respective folder.
When a plugin is edited, the chances of the file being updated as well are higher compared to one general file which might be overlooked.

If you want to have a single overview file, it could be compiled from the other markdown files. We could make a bash script in the root directory with the script ready to execute.