Merge pull request #1 from borisyankov/master

Updating to master.
Added extensibility point for templates.

This allows named templates to be added, for example:

    interface HandlebarsTemplates {
        specialListOfThings: HandlebarsTemplateDelegate;
    }

So the strongly typed version can be used.

    var template = Handlebars.templates.specialListOfThings;
Merge pull request #2557 from Steve-Fenton/master

Added extensibility point to Handlebars templates.