introduce perses object in package.json and change the way the archives are created

[Nexucis]

This PR introduced a new file TYPE where you can write the type of the plugin (panel, query, datasource, variable)

It also changed a bit how the archive are built.
The archive contained now the file TYPE, the README.md and of course the content of the dist folder

And it also remove any additional folder that was at the root of the archive and that wasn't necessary.
The archive name contains also the version of the plugin.

Should be merged after #6

[jgbernalp]

would it be better to create a plugin.json file so we can include other metadata, such as author, version, etc?

[Nexucis]

I'm wondering if it makes sense since these metadata info can be found in the package.json already.
Perhaps we can include the package.json in the archive as well.

[Nexucis]

Having a specific json file for the plugin could be interesting if we have info that cannot be found in the package.json or in the file mf-manifest.json

[jgbernalp]

Then we could use the package.json with a custom field perses if we need to include more metadata as the package.json should hold already the version of the plugin and author. We can add there the plugin type like:

perses:{
  pluginType:"panel"
}

WDYT?

[Nexucis]

ah yeah I like this idea. Will make the changes ! Thanks 🙏

[Nexucis]

done