Remove a bunch of Not implemented functions. And unused headings.

Also removes the code section numbering since it is no longer accurate.

I'll add a section to the wiki of all the NIE localarray functions which
were removed so that we can implement them later.
Remove tests for notimplemented methods.
Merge pull request #333 from cowlicks/remove-nie

Remove a bunch of Not implemented functions. And unused headings.
local_array -> ndarray