Separated crawling functions out to separate class. Modified some RemoteObject behaviors. Current functionality: gathers all remote objects, but doesn't try to instantiate any ImportObjects yet.
Fixed a mistake that made get_import_objects include an ImportObjects among the RemoteObjects it's supposed to return. (Need to rename that method\!)
Moved the crawling functions out to the Crawler class.
Got more careful about how HTTP errors are handled, including recognizing when we're redirected to the login page.
Merge branch 'crawler' into devel