Permission error on macOS

[balazsbotond]

I've built the app on macOS. The resulting .dmg looks OK but after installing it in the Application folder and opening it I get the following error:

I might have some time later this week to debug this and send a PR but if someone can fix it in the meantime, I'll be glad to help by testing it on my Mac and building a binary.

Btw, awesome app, thank you!

[Physiix]

The problem is that path.resolve('.') returns the current directory for Windows and Linux, but /(root) for mac.
With the latest commit, for mac, the database is saved in ~/.topsi/data/database.json.
I added a zip for mac in the release https://github.com/Physiix/topsi-project-manager/releases/download/v0.1/Topsi-macos-portable.zip

Thanks, and please let me know if it's working.