Added check if vim instance is already running

[theaino]

When running multiple neovim instances, an error always pops up when opening neovim.
This is kind of annoying.
It is easily removed by checking a variable for nil.

[jiriks74]

Hello,
if you'd like you can transfer this PR to my repository and we can take a look at it.

BUT DO NOT POST IT THERE AS IS!

Please redo this again without formatting the whole codebase. Your changes are unreadable and I won't be merging them like this. My repository uses StyLua for code formatting so use that if you need formatting or turn off formatting in your editor.

I'll be tracking this PR here.

This repository seems to be completely dead so I'm trying to fix some things and merge contributions. If you'd like to see a rough plan of what I want to do you can look at my OpenProject instance.

[theaino]

Just checked; apparently you have already implemented this in your repo 😅

[jiriks74]

Just checked; apparently you have already implemented this in your repo 😅

I'm not aware of doing so but I'm glad that your requested functionality is already implemented.