Uplift plugin to latest practices

## Features

- Refactoring of plugin code to adhere to latest jQuery development practices
  - Wrapping code in a Immediately Invoked Function Expression to protect the $ alias / add scope
  - Adding default options for speed and an offset from the anchor to apply; applying an offset will suppress the addition of a hash to the URL; this may address Issue #1 though I don't know if this is the issue author's desired behavior...
  - Moving example HTML into its own directory
  - Moving plugin file into root of project
- Adding a bower.json file with the intention to ideally have this plugin listed in the bower.io registry

## Breaking Changes

- This update removes the explicit call to `$('.selector').anchorAnimate();` in the plugin code; you must now invoke this method manually. Allows you to override the default settings as desired.