Hiding such environment variable prevent easy access to the user
owning the software or the user owning the instance.

Some instances needs to have the actual username of the instance in their
config files and some softwares needs access to the username of user
building the software. This is - in theory - easy to do in zc.buildout
thanks to https://collective.github.io/collective.recipe.grp/ , but the
way slapos run buildout with some environment variables hidden made it
not possible.

Fixes [#20180402-716ACB](https://nexedi.erp5.net/bug_module/20180402-716ACB/)

/reviewed-on !41

Authored by "Hugo Ricateau"

python promises can define sense, test and anomaly method.
test method will be called by slapgrid or when no bang is needed for the promise anomaly method is
called when a promise failure required to bang the master, anomaly method can be optional but it's not the case for test method.

Slapgrid always run promises and save the result in .slapgrid/promise/result in a JSON format. The result will be used later by monitor
When a partition is correctly deployed, slapgrid will only run promise anomaly and will bang if there is an error and if the failed promise can bang

check promise anomaly when partition is upto date

Sort paths on the template_keep_last_workflow_history_only_path_list.

Reimplement the Creation of Trial Request to be compatible with renderjs/jio approach. Use Trial Condition for define what are the trials available to be requested.

On the core of SlapOS for a full autonomous deployment, it is required frontend and re6st normally. Include initial products for make easy the user to deploy it.

By "delete" is done by close Assigments or Invalidating Documents.

Obviously It was a horrible idea :)