Support for number parsing

[Merwer]

Added support for providing options when serializing forms. Options are used to ensure that default functionality continues as is.

Current options include an option to define how various <input> types are encoded. There was already functionality to convert checkboxes into booleans, but now that feature can be turned on/off. In addition, a new encoding option is added to support converting <input type="number"> into an integer.

var serializeOptions = { 'encodes': { 'checkbox': true, 'number': true } };
var $form = $(document.querySelector('form'));
var obj = $form.serializeObject(serializeOptions);

[gubi]

Please merge this feature