Fix Bug with DOM Update and {{_this}}

We added a new method called tApp.getComponentFromDOM(domElement), which finds the component associated with the DOM object. All calls to {{ _this }} use this method. Instead of just scanning the current element to see if it is a component, it continues to scan up the tree until it finds a component in case the element is not the main element of the component.

Additionally, there was a DOM update bug associated with inserting text nodes, which has now been fixed.