Don't take ts as peerDependencies

This is not actually required, especially when the plugin is used in an editor setting

package.json

@@ -29,8 +29,5 @@
     "mocha": "^5.2.0",
     "tslint": "^5.11.0",
     "typescript": "^3.1.3"
-  },
-  "peerDependencies": {
-    "typescript": ">= 2.3.1"
   }
 }