Disable ts-checks on output files

This would disable ts checking on the whole file for all output files to enable usage of `"importsNotUsedAsValues": "error"`. If needed I could spend some more time to make the change only target the imports, but since both tslint and eslint are disabled for the whole file I figured this could be an acceptable solution.

Fixes relay-tools#177

Author: AnotherHermit

src/formatGeneratedModule.ts

@@ -24,6 +24,7 @@ export const formatterFactory = (
   }
   return `/* tslint:disable */
 /* eslint-disable */
+// @ts-nocheck
 ${hash ? `/* ${hash} */\n` : ""}
 ${documentTypeImport}
 ${typeText || ""}