[Enhancement] Refactor of license django model (#187)

Fixes #119

Licenses are now created in the bootstrap management command. To only create the licenses use the command line argument `-ol` or `--only-licenses`.
These licenses are then fetched by there `cc_string` when adding a license to a package.

Co-authored-by: Liam Brydon <62733830+MyCreativityOutlet@users.noreply.github.com>
Co-authored-by: jebus <lorsbach@envipath.com>
Co-authored-by: Tim Lorsbach <tim@lorsba.ch>
Reviewed-on: enviPath/enviPy#187
Co-authored-by: liambrydon <lbry121@aucklanduni.ac.nz>
Co-committed-by: liambrydon <lbry121@aucklanduni.ac.nz>

utilities/misc.py

@@ -714,6 +714,7 @@ class PackageImporter:
             license_obj, _ = License.objects.get_or_create(
                 name=license_data["name"],
                 defaults={
+                    "cc_string": license_data.get("cc_string", ""),
                     "link": license_data.get("link", ""),
                     "image_link": license_data.get("image_link", ""),
                 },