Remove unnecessary files from built

Gaucho built have some unnecessary files that could be removed to (slightly) reduce built size and overall cleanup:
* app/test folder
* Original source code for both public and main (removing this would required a transpilation/move of main code)
* Pull request template and contributing files
* Unnecessary resources/logos
* Consider bundling vue and front dependencies with parcel (https://parceljs.org/cli.html#target) and remove them from package.json to reduce size (parcell will compress the dependencies)

Steps to see built version:
* npm run pack
* In dist/linux-unpacked/resources --> npx asar extract app.asar unapcked_app