Correct / work around imports and dylink imports to keep overridden Repy calls overridden.

Multiple libraries do `from repyportability import *`. This re-imports
(and thus restores to their original forms) all Repy API calls.

Additionally, cleaned up the code a little.
Use `dy_import_module` imports, clean up code.
Cleaned up imports and styled code.
Removed repyportability import. I see no reason why it should be there.
In seash_helper.py: enabled Affix for sockettimeout; cleaned up imports; improved code style.

The biggest problem here is that we require a library that is also
used by the Affix framework, `sockettimeout.r2py`. If Affixes are
enabled, they will import that library, and its functions will
bind to the original Repy network calls. Yet, when we import it,
we want its functions to use the Affix'ed versions of the calls!
The hack I came up with is that I use one of `sockettimeout`'s
wrapper functions on a socket that I get from an overridden,
Affix-enabled `openconnection` call (instead of
`sockettimeout.timeout_openconnection` which will use the original
Repy `openconnection`).

Cleanups relate to using `dy_import_module` rather than the
`...symbols` version so we import libraries only once, and
associated adding of module names to function calls.
Also cleaned up a bit of sub-indentation.
Remove debug statements and outcommented outdated stuff.
Corrected import in module clearinghouse's `command_callbacks.py`
Replaced seattle.cs.washington.edu with current URL seattle.poly.edu
Lots of cleanup from new imports.
Cleanups from new imports; also removed a debug statement.
Workaround to enable Affix'ed nmclient; plus cleanups from new imports.
Merge commit 'e7450c3'