Allow for multiple template paths

[cowboyd]

For frameworks like cells that don't use standard template paths, I've added the ability to search multiple paths for your mustache templates. The array of search paths is stored in Mustache::Rails::Config.template_paths and the current template_base_path is always the first entry in this array.

That way, you can do things like this:

Mustache::Rails::Config.template_paths << "app/cells"

I also changed it to raise a MissingTemplate if the mustache file could not be found rather than Errno::ENOENT which what it's currently doing.

thanks for a great plugin!

cheers, Charles

[jocubeit]

Nice. Would love to see this merged.

[myobie]

+1 on getting this merged