tree-sitter: 1.18.2 -> 0.19.3

Update the grammars and add `allGrammars` derivation.
`nix-build "<nixpkgs>" -A tree-sitter.allGrammars` will create a
derivation with symlinks to all the grammars

pkgs/development/tools/parsing/tree-sitter/grammars/tree-sitter-c-sharp.json

@@ -1,9 +1,9 @@
 {
   "url": "https://github.com/tree-sitter/tree-sitter-c-sharp",
-  "rev": "21ec3c3deb4365085aa353fadbc6a616d7769f9f",
-  "date": "2021-02-18T09:41:56-08:00",
-  "path": "/nix/store/8172rv05dvvlyp4cfmr2b41g4a20vlcf-tree-sitter-c-sharp",
-  "sha256": "1cc0ss09bfv2xy77bpcmy6y2hqis7a8xby9afcaxcn5llj593ynj",
+  "rev": "70fd2cba742506903589b5e046c32e0e3e06404a",
+  "date": "2021-03-03T17:18:54-08:00",
+  "path": "/nix/store/m0pzbb0vg0fm9nycj05ay0yldzp7qwbi-tree-sitter-c-sharp",
+  "sha256": "12jj66rsn1klsk24yj0ymgsqwy7lc5kb3nkj7griip8rmi3kgy41",
   "fetchSubmodules": false,
   "deepClone": false,
   "leaveDotGit": false