Log the parser we're using at run time

Similar to the approach we took for Radon, this is helpful output to
guide users who might need babel toward the info they would need.

Author: Will Fleming

bin/eslint.js

@@ -16,6 +16,8 @@ var cli = new CLIEngine(options);
 var debug = false;
 var checks = require("../lib/checks");
 
+console.error("ESLint is running with the " + cli.getConfigForFile(null).parser + " parser.");
+
 // a wrapper for emitting perf timing
 function runWithTiming(name, fn) {
   var start = new Date()