web: add UI to remove tags when viewing messages

Cargo.lock

@@ -1440,6 +1440,11 @@ version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "df3b46402a9d5adb4c86a0cf463f42e19994e3ee891101b1841f30a545cb49a9"
 
+[[package]]
+name = "human_format"
+version = "1.0.2"
+source = "git+https://github.com/wathiede/human-format-rs#c5f59f0b0e4d92e649d415a8509bc46e92413356"
+
 [[package]]
 name = "hyper"
 version = "0.10.16"
@@ -1727,6 +1732,7 @@ dependencies = [
  "console_log",
  "gloo-net",
  "graphql_client",
+ "human_format",
  "itertools",
  "log 0.4.20",
  "notmuch",