poor version of Each content-calling
remove old file
augment->include, no more "implicit augment"

It's just too useful for Component constructors to be
callable as functions:

Each.create({content: Template.foo})

// in impl of Each's render:
buf(this.content(function () { return 3; }))

With implicit augment, `this.content(…)` would augment Template.foo.

Also, there was the ever-present danger of someone omitting `new`,
which we couldn't detect.

Now `new Foo(…)`, `Foo(…)`, and `Foo.create(…)` are all equivalent.
nicer Each impl