Add support for Zepto (requires event and data modules only).  First step to fully convert to native.
Started converting to native javascript.

Working:
*  validation
*  array, multiple, object, select, integer, number, and string editors
*  html theme

Not working yet:
*  table, enum, null editors
*  bootstrap, foundation, and jqueryui themes
*  iconlibs
*  need non-jquery implementations of $.each, $.extend, and el.data
*  need way to instantiate and use the api without $.fn.extends

Also, needs a lot of testing and performance benchmark results against the existing jquery version.
Add native implementation of $extend (http://andrewdupont.net/2009/08/28/deep-extending-objects-in-javascript/)
Added native implementation of $.each and moved utilities to their own file.
Convert table, null, and enum editors to native javascript.
Convert bootstrap2 and bootstrap3 themes to native javascript.
Convert foundation themes and iconlibs to native javascript.
Fully remove jQuery dependency.
Performance improvements and a few bug fixes.

$extend wasn't checking for plain objects correctly, which was causing a lot of overhead trying to copy instances of JSONEditor.
Borrowed jQuery's isPlainObject code to fix this.

The `set` and `change` events were firing much too frequently during initialization for string and select editors causing slow downs.
Convert jqueryui theme to native javascript.
A bunch of bug fixes, performance improvements, and new api methods.

Bug fixes:
-  watch listeners not always firing
-  collapse button in array editor replaced with span when toggling
-  collapse button in array editor added extra line break when toggling
-  collapsed option broken for arrays

Performance improvements:
-  only a single 'change' event is now fired for each interaction with the form, regardless of interrelated templates, etc.
-  replaced internal DOM events with simple method calls when bubbling up changes.
-  simplified watched fields logic

New API methods:
-  watch, unwatch - Get alerted whenever a specific field changes

  ```js
  editor.watch('path.to.field',function() { /*...*/ });
  editor.unwatch('path.to.field',my_function);
  ```

-  getEditor - Get a reference to editor objects

  ```js
  var mystring = editor.getEditor('path.to.mystring');
  mystring.setValue('test');
  console.log(mystring.getValue());
  ```
Add backwards compatible syntax for setting JSON editor defaults.
Add api methods for listening for ready/change events.

```js
// Listen for an event
editor.on('change', function() {});

// Stop listening for an event
editor.off('change', my_function);

// Remove all listeners for an event
editor.off('change');

// Remove all listeners for all events
editor.off();
```

The jQuery wrapper emits DOM events like before, so there is no change there.
Fix bug with oneOf and registering editors.

Each oneOf editor was registering itself, even if it wasn't the current editor.
This was causing problems if two oneOf schemas shared a property.
Update README and examples. Fix a couple bugs.

There was a bug with setting the value of the multiple editor programatically.
Add filesize for production version to readme.
Miscellaneous bug fixes for edge cases.
version bump
Fix script src in validator test page.
Merge pull request #76 from jdorn/native_javascript

Version 0.5.0 - Remove jQuery dependency, new api, performance improvements