Import upstream v0.16.22, stripped

Upstream commit: 474dd0229cb20cf513036619781ed97bd8073c3f
Enterprise-only files removed or emptied: 63
Enterprise-only snippets removed: 117 in 50 files
Dangling module declarations removed: 5
Cargo edits turning enterprise off: 14
Verification: clean
Enterprise feature gates left for rebuilt features: 19 in 18 files

Produced by tools/fork/strip.py. The full report is in docs/fork/strip-reports/ on main.

tests/resources/jmap/email_set/minimal.json

@@ -0,0 +1,7 @@
+{
+    "receivedAt": "2018-07-10T01:03:11Z",
+    "sentAt": "2018-07-10T11:03:11+10:00",
+    "messageId": [
+        "my-message-id"
+    ]
+}