first endnotes implementation
notes-related methods in api.Document
rename endnotes.py to notes.py
fixes
style attributes, styles iterator
proper document parts for notes, nose tests for notes
run endnote_reference and footnote_reference properties
remove work notes
move NoteReference to docx.text to prevent circular imports
don't set a notes part if none exist in the document
run elements, notes changes
Merge commit 'refs/pull/53/head' of https://github.com/python-openxml/python-docx into better-lists-fonts-links-support

Conflicts:
	docx/oxml/__init__.py
	docx/oxml/parts/styles.py
	docx/oxml/text.py
	docx/text.py