Willem de Jong - 2010-01-31

I published a new version with a few bug fixes on github - http://github.com/willemdj/erlsom.

- corrected erlsom_add to deal with type hierarchies
- fixed problem with type hierarchy
- fixed problem with import in include
- accept id attribute in schema element
- remove obsolete guards
- fixed problem with attribute groups
- fixed problem with whitespace in text elements