Adding order-bys.

These come in the form of two actions @order_ascending and @order_descending. Both can take either a field name or an array of field names.
Updating readme.
fixing markup
While I'm here, fix the next li to be consistent with the previous oens
Merge branch 'master' into orderby
Changing the order-by spec.

There's now a single @order_By element. It takes a single orderby element or an array of them, where each orderby element is a string (field name for ASC) or a map of {fieldname : "asc|desc"}
updating readme
Merge pull request #4 from akiban/orderby

Adding order-bys.