Replace section 4.1 with section A.3.
The new section 4.1 is titled "Naming and binding." It includes the
text of section A.3 augmented with some of the detailed text from the
old section 4.1.
The \dfn, \index stuff is probably wrong, but I tried.
Also update other parts of appendix A to mention that nested scopes
and generators are standard features.
Add new opcodes LOAD_CLOSURE, LOAD_DEREF, STORE_DEREF, MAKE_CLOSURE to
docs for dis module.
Add docs for new function and code members in Sec. 3 of ref manual.
They're present regardless of whether nested scopes are used.
Remove description of default argument hack from Sec. 7 of the ref
manual and refer the reader to the appendix.
Jeremy Hylton
Fred Drake
Michael W. Hudson