Rename plugin file using standard jQuery plugin naming scheme

SVGMagic.js is now jquery.svgmagic.js
Add examples/test HTML document

This may be used to see how the plugin is used, as well as a crude verification
that the plugin is working (by loading this page and inspecting the HTTP request
to the remote API).

* Tests replacement of <img> using an SVG src

* Tests non-replacement of an <img> with non-SVG src

* Tests replacement of a CSS background-image
Trivial change: Add inline documentation for options

This documents the options within the JavaScript source file.
Add project reference to JSON3 (JSON polyfill)

SVGMagic depends upon JSON support (it is used internally by jQuery's JSON
deserialisation of the remote server response).  Currently a JSON polyfill
(Douglas Crockford's "json2") is included as part of the SVGMagic script body,
but it could easily be included externally.  This tracks a suitable polyfill
project as a git submodule.
Remove "json2" polyfill from the SVGMagic script body

This was Douglas Crockford's 'json2' polyfill, originally available at:
https://github.com/douglascrockford/JSON-js/blob/master/json2.js

A link to the JSON3 polyfill has already been added to this project.  If JSON is
not supported by the target browser then the JSON polyfill should be included.

This could be accomplished using a framework such as Modernizr, detecting JSON
support and adding the polyfill if it's not there.
Trivial & minor fixes to the JavaScript source file

Fix a minor syntax error (missing semicolon) and move a brace to the
next line for readability.
Add replacement options which are drop-in replacements for deprecated ones

Some of the options could be named a little better; making a little more obvious
what they do.  This adds new names for some of those options and deprecates the
old names.  For compatibility purposes they will still continue to function.

* Alter example/testing HTML file to reflect new API.
Resolve #15 - Plugin now supports chaining by returning 'this'

See https://github.com/dirkgroenen/SVGMagic/issues/15
Complete refactoring of the plugin body - add support for new options

The plugin body has now been just about completely rewritten, mainly for clarity
and modularity of operations.

* Expected to see some minor performance improvements.

* Switching to Regex for detecting SVG files.

* Mass variable declaration, in order to improve the benefit gained by putting
  this script through a minifier service, such as Google's closure compiler.

* Introduce new callback mechanism, similar to old 'callback' option but passing
  a parameter (the array of image replacements) to the callback function.

  * The old callback mechanism still functions for backwards-compaibility but is
    deprecated.

* New configuration/options have been introduced which control the endpoint of
  the remote request in order to retrieve PNG replacement URIs.  This is likely
  to largely resolve #9 - https://github.com/dirkgroenen/SVGMagic/issues/9
Merge feature branch for project reorganisation
Update documentation & bump version number
Merge branch 'release/2.4.0' into production
Merge tag 'v2.4.0'

Refactoring and enhancements