Re-consider compressing assets using cssmin/jsmin

[jelly]

The configuration needs to be updated to:

-# Static files backend that allows us to use far future Expires headers
-STATICFILES_STORAGE = 'main.storage.MinifiedStaticFilesStorage'
+STORAGES = {
+    "default": {
+        "BACKEND": "django.core.files.storage.FileSystemStorage",
+    },
+    "staticfiles": {
+        "BACKEND": 'main.storage.MinifiedStaticFilesStorage'
+    },
+}

Then we should consider if we keep this and revive cssmin support with rcssmin.