Add api-extractor

Author: jakebailey

.gitignore

@@ -41,6 +41,7 @@ scripts/eslint/built/
 scripts/debug.bat
 scripts/run.bat
 scripts/word2md.js
+scripts/apiExtractor.js
 scripts/buildProtocol.js
 scripts/ior.js
 scripts/configurePrerelease.js

package-lock.json

@@ -39,6 +39,7 @@
         "!**/.gitattributes"
     ],
     "devDependencies": {
+        "@microsoft/api-extractor": "^7.30.0",
         "@octokit/rest": "latest",
         "@types/async": "latest",
         "@types/chai": "latest",

package.json

@@ -0,0 +1,15 @@
+import * as path from "path";
+import {
+  Extractor,
+  ExtractorConfig,
+  ExtractorResult
+} from "@microsoft/api-extractor";
+
+const packageRoot = path.resolve(__dirname, "..");
+
+// TODO(jakebailey): call api extractor for:
+//   - src/typescript
+//   - src/typescriptServices
+//   - src/tsserverlibrary
+// Then in the output, replace const enum with "enum".
+// Also apply copyright header, as api-extractor won't.