Configure Pulp ALLOWED_IMPORT_PATHS and ALLOWED_EXPORT_PATHS

[ianballou]

Import/export functionality fails unless Pulp is configured to allow exporting to /var/lib/pulp/exports, for example. foremanctl should configure the same import/export locations as Katello admins are used to.

Example from my forklift Katello development box:

ALLOWED_IMPORT_PATHS = ["/var/lib/pulp/sync_imports", "/var/lib/pulp/imports"]
ALLOWED_EXPORT_PATHS = ["/var/lib/pulp/exports"]

Excerpt from puppet-foreman_proxy_content:

https://github.com/theforeman/puppet-foreman_proxy_content/blob/e942c0956c25106585e2da2538efea8a61a7594a/manifests/init.pp#L151-L152

Users should be allowed to configure these values via foremanctl so that they may export to different filesystem locations and import from custom locations.

[ianballou]

In Katello today, users can direct Pulp to import and export from specific filesystem locations. For export, it is via the pulpcore_export_destination setting. For import, there is a path parameter passed in via the API.

[evgeni]

Fixed in #455