use more specific nodes for open tag

[patricklx]

there are now also following nodes:

• name node: PathExpression
• start tag node: Element openTag span

example:

/*
  <Foo.bar.x attr='2'></Foo.bar.x>
   ^-------- Element PathExpression node
  ^------------------ Element openTag span
                      ^----------- ElementEndNode
 */

afterwards completions/validations can be add for attributes and element tags
In #663

[NullVoxPopuli]

Seems good to me