V1: Remove templating; consolidate to core.clj{s}

This pull request proposes significant changes of the dommy API and internal structure. We have decided to remove the templating features of dommy in order to keep dommy small and simple to use and maintain. While dommy's templating has been useful in the past, removing it from the library vastly simplifies the internal namespace structure and resolves some outstanding issues.

From what we have seen at Prismatic and around the community, dommy's core value is in DOM event binding, query selection, and getting & setting element attributes. While we feel that there are plenty of alternative templating solutions available today, if anyone would like to maintain these features in a separate repository, please let us know.

## Changes
* Updated ClojureScript, lein-cljsbuild and clojurescript.test dependencies
* Removed all templating-related code (`node`, `deftemplate`, etc.), and removed `dommy.template` ns
* Functions no longer coerce "node-like" parameters to dom nodes
* Moved all functions from `dommy.attr` to `dommy.core`
* Renamed `dommy.macros` to `dommy.core`, allowing for:
```clj
(ns foo
  (:require [dommy.core :as dommy :include-macros true]))
```
* Renamed `dommy.core/ancestor-nodes` to `dommy.core/ancestors`
* Added `dommy.core/create-element` and `dommy.core/create-text-node` to make up for removing `node`
* Moved implementation-specific code to `webapp.utils` (for both clj and cljs)