tree-sitter: 0.15.7 -> 0.16.4

Includes some bugfixes/cleanups to the scripts and packaging, a run of the
updater, a bump of the version, an upgrade to the newer cargo fetcher in #79975,
and gets the web assembly portion to compile successfully.

Fixes #75863

pkgs/development/tools/parsing/tree-sitter/grammars/tree-sitter-rust.json

@@ -1,7 +1,7 @@
 {
   "url": "https://github.com/tree-sitter/tree-sitter-rust",
-  "rev": "3f956b18a6b0a576ed238cc69d5e3f413bd547b1",
-  "date": "2019-07-18T11:44:02-07:00",
-  "sha256": "0dwxg3pqirqm1lvl5x0q9djavfri9ffk5diygqzjnx53rwqhyzj8",
+  "rev": "1c37782a5528979a22991f8ed50dd3d3e423ac92",
+  "date": "2020-01-20T16:08:51-08:00",
+  "sha256": "04fzzn2rxpfg7pwymmarkdjabbp20yp10yzr4a5a1xcqx8hky9ix",
   "fetchSubmodules": false
 }