Use slapos.recipe.template instead of slapos.recipe.template if possible

Harmonize template keys :
rendered -> output
template -> url
template = inline: -> inline =

Delete "mode" key

See merge request nexedi/slapos!1151

Adapt all promise sections to changes in plugin promise recipe.

Apps where downloaded during "slapos node instance" step, which has several
problems:
 - first, instance step is not supposed to require network access
 - this was downloading "latest" version of the app, which made the software
   not reproductible
 - since a few weeks this was no longer working, as we could see in test results

done with:

     npm install
     git ls-files | grep -v '\/unstable\/' | xargs ./node_modules/.bin/eclint fix
     git ls-files | grep buildout.hash.cfg | xargs ./update-hash

This promise check if nextcloud app was correctly deployed, it ensure that slapos instance will deploy until nextcloud install succeed.

/reviewed-on !676

Fix nextcloud backup cron frequency
Fix apache graceful script path