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.
Add rope related files to gitignore.
local_array -> ndarray
Merge pull request #334 from cowlicks/gitignore-rope

Gitignore rope
Merge pull request #335 from cowlicks/local-array-to-ndarray

local_array -> ndarray
Put client side modules in distarray/client/ and change imports.
move client.py -> distarray.py and change imports to reflect this.
move DISTARRAY_BASE_NAME into top level __init__.py

This is because dacluster should not have to impor distarray/client/ to
clean things up.
Fix circular import issue with distarray.py
client_maps.py -> maps.py. add __future__.absolute_import where needed.

Since the module distarray/client/distarray.py's name conflicts with the
package name we import `absolute_import` everywhere in the file.
rename client directory to dist