initial idea for how using tags will look

/cc @ianstormtaylor this is working, using the new tags dsl idea

it would get cleaned up / simplified more once we can remove `.load` entirely (after we merge the other 2 prs)
gotcha. i think AdWords looks like it has a single one that got named. i'm +1 to either having multiple and naming all, or having one and not naming it. but then if there are multiple we shouldn't leave one unnamed