Better fix for passing integer to ``range``
Fix for string base types and accompaning unit test
Making ``pydap.tests`` a shared namespace
Run tests from `pydap.tests` instead of `pydap/src`

I changed the default behavior in nose so that the tests are run from
the `pydap.tests` module, instead of running from the directory
`pydap/src`. This allows testing 3rd party packages that also have tests
in the shared namespace.

I'm not sure if this is a good thing, since the test suite now is not
restricted to the module. The good side is that it allows us to test all
handlers/responses from a single location, which is good IMHO. On the
other hand, unit tests may fail even if pydap is correct.
File for sharing the namespace `pydap.tests`
Revert default test option to be directory based

After thinking about this, I think it's better to test only pydap by
default. We can always tests all the modules by running nose with the
package module.
Changed the way `close` works

I've redesigned the way the `close` method works. The idea behind the
method is that handlers sometimes will want to close a dataset after the
request is completed. For example, the NetCDF handler will open the
file, leaving it open until the request/response cycle is complete. In
order to do this, the handler defines a `close` method that closes the
file pointer.

To call the method, the base handler will assign the method it to the
response application created. Webob will then take care of calling
`close` after the request/response cycle.