func_unit.html(html, callback) -> String|funcUnit
{optional:String|Function}
If provided uses this as a check before continuing to the next action.
{optional:Function}
a callback that will run after this action completes.
{String|funcUnit}
if the html parameter is provided, returns the funcUnit selector for chaining, otherwise returns the html of the selector.
Gets the html from an element or waits until the html is a certain value.