fix(cli): allow passing the config file before the options

The cli usage says:
> USAGE: protractor configFile [options]
However, the options passed as argument are merged into the default
configuration as soon as the configFile is met in the args parsing
loop.
This fix merges the options in the default configuration only after
the loop, allowing to pass the options to the cli before or after,
or around the config file.

lib/cli.js

@@ -9,7 +9,7 @@ var SauceLabs = require('saucelabs');
 var glob = require('glob');
 
 var args = process.argv.slice(2);
-var configDir;
+var configDir, configPath;
 
 var merge = function(into, from) {
   for (key in from) {
@@ -230,14 +230,15 @@ while(args.length) {
       commandLineConfig.jasmineNodeOpts.isVerbose = true;
       break;
     default:
-      var configPath = path.resolve(process.cwd(), arg);
-      merge(config, require(configPath).config);
-      merge (config, commandLineConfig);
+      configPath = path.resolve(process.cwd(), arg);
       configDir = path.dirname(configPath);
       break;
   }
 }
 
+merge(config, require(configPath).config);
+merge(config, commandLineConfig);
+
 var sauceAccount;
 if (config.sauceUser && config.sauceKey) {
   sauceAccount = new SauceLabs({