chore: add Typescript support

Fixed: twpowertools:198
Change-Id: I00a14ab8ad93e9ff8d2a4d2e33824a9290500a8a
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..3c671ac
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,12 @@
+{
+  "compilerOptions": {
+    "sourceMap": true,
+    "noImplicitAny": true,
+    "noImplicitReturns": true,
+    "noFallthroughCasesInSwitch": true,
+    "module": "es6",
+    "target": "es2019",
+    "moduleResolution": "bundler",
+    "allowJs": true
+  }
+}