Revert shellscript grammar change and add more tests

extensions/shellscript/cgmanifest.json

@@ -4,13 +4,14 @@
 			"component": {
 				"type": "git",
 				"git": {
-					"name": "jeff-hykin/better-shell-syntax",
-					"repositoryUrl": "https://github.com/jeff-hykin/better-shell-syntax",
-					"commitHash": "b0eddf9fcf46a7bbd375366fc8052bd23fd5992b"
+					"name": "atom/language-shellscript",
+					"repositoryUrl": "https://github.com/atom/language-shellscript",
+					"commitHash": "4f8d7bb5cc4d1643674551683df10fe552dd5a6f"
 				}
 			},
 			"license": "MIT",
-			"version": "1.2.9"
+			"description": "The file syntaxes/shell-unix-bash.tmLanguage.json was derived from the Atom package https://github.com/atom/language-shellscript which was originally converted from the TextMate bundle https://github.com/textmate/shellscript.tmbundle.",
+			"version": "0.28.2"
 		}
 	],
 	"version": 1

extensions/shellscript/package.json

@@ -9,7 +9,7 @@
     "vscode": "*"
   },
   "scripts": {
-    "update-grammar": "node ../node_modules/vscode-grammar-updater/bin jeff-hykin/better-shell-syntax autogenerated/shell.tmLanguage.json ./syntaxes/shell-unix-bash.tmLanguage.json"
+    "update-grammar": "node ../node_modules/vscode-grammar-updater/bin atom/language-shellscript grammars/shell-unix-bash.cson ./syntaxes/shell-unix-bash.tmLanguage.json"
   },
   "contributes": {
     "languages": [