Add url escaping with jq, support nested notes.

[sidequestboy]

Adds dependency of jq for escaping of spaces and special characters in markdown filenames.

Adds support for nested files.

[sidequestboy]

Maybe nested files were working before actually, but spaces in filenames was definitely broken!

I am unsure you want to add jq as a dependency, but it seems like a small dependency anyway.

(Alternatively, maybe you could just at least call string.gsub to %-encode the spaces)

Also, I investigated curl's ability to url-encode, but that seemed limited to query data (see here)

[oflisback]

Thanks a lot for your investigation and PR! This must be fixed and I agree about checking what alternatives there are before adding another dependency. Looking forward to try this out later today.

[oflisback]

I pushed an alternative solution to the uri encoding problem: 6368d1b

Do you also think this is a good enough approach?

[sidequestboy]

That looks great! I tested and it works for my case, it's nice to not add an external dependency for something so small too