Permit selecting storage service internal as a location type

refs #6819
Do not recreate internal space if one already exists

Previously, if the storage service internal location was changed to a
new location, this startup function would create a new one at the
default path. This now only tries to make a new internal location if
none exists at all.

refs #6819
Add email notification for deletion requests, fixity failures
Add link to download packages from Packages tab

refs #6929
Roughed in AIP recovery model functionality.
Added endpoint to submit recovery requests to.
Refactored delete/recover endpoints.
Added AIP request administration to UI.
Refactoring AIP request handler.
Removed setting used during testing. Got recovery working.
Added corrupt files backup during AIP restore.
Setting for where bad AIP files get backed up.

Added a setting allowing the directory where bad AIP files should be
copied to to be specified.
Added warnings if AIP restore backup dir not set.
Added deletion of temp package.
Fixed issue caused by refactor.
Added auto-create recovery location.
Fixed issue with request descriptions.
Fixed recover request approve issue.
Fixed two small issues.
Got rid of setting and added dir creation.

Got rid of the recover_backup_path_within_location setting and added
auto-creation of the recover and recover/backup paths within the
internal storage space.