Enhancements of the JSP parsing API, which would allow 
implementation of the tag usage features, improvements of 
code completion and similar. 

The enhancements include:

- Return from the JSP parser the context of a particular 
element, so the code completion can filter out items which 
are not appropriate.
- Return location of the taglib directives, so the editor 
can easily find a suitable place in the text to add 
additional taglib directives.
- Return encoding of the document, so the editor can load 
it using the correct encoding.
- Return a list of tag libraries in the web module, so the 
tag usage code knows which are already included.