Warn user if config-userfrosting.php is missing

[Netrilix]

The new default install uses config-userfrosting-example.php instead of config-userfrosting.php. This is a good idea because it forces users to examine the config file before they run the program for the first time. However, I think index.php should give a quick explanation of what to fill out in the config, and that they need to rename it to get rid of -example.

As it stands right now, an initial run of 0.3.1 will produce nothing but a PHP error page about missing a required include file, which is an ugly thing for a new user to see.

[alexweissman]

How about if we just link them to the updated installation guide?

[Netrilix]

That'd probably be sufficient if you can add an anchor at Step 4: Create Database and Setup Configuration File and link directly to it.

[alexweissman]

Ok, added in hotfix 0.3.1.4.