added get method to Space resource
added get method to Space resource

This was achieved by extracting a generic request method.
It was also necessary to modify the callback to pass the space resource
(rather than the last constituent) to the user.

FND/tiddlyspace,FND/tiddlyspace,FND/tiddlyspace,TiddlySpace/tiddlyspace,TiddlySpace/tiddlyspace,TiddlySpace/tiddlyspace