[nm-wg] updates to hierarchy document

[Bruce Lowekamp <lowekamp@cs.wm.edu>]

The hierarchy document has been updated in response to all of the comments 
we received.  Many thanks to those who read the documents and made 
comments.  A number of issues were identified and fixed.

The updated version is on the NMWG website, 
<http://www-didc.lbl.gov/NMWG/>, under current documents.  There is the new 
version (pdf with changebars) and the "responses to comments," which is a 
collection of all comments made on gridforge with responses from the 
authors.

Please give it a readthrough, especially those who made comments before. 
We hope to upload a revised version to gridforge next week.

Bruce