thirdparty: port zope.interface to relative imports...
thirdparty: port zope.interface to relative imports
By using relative imports, we're guaranteed to get modules
vendored with Mercurial rather than other random modules
that might be in sys.path.
My editor strips trailing whitespace on save. So some minor
source code cleanup was also performed as part of this commit.
# no-check-commit because some modified lines have double newlines
Differential Revision:
https://phab.mercurial-scm.org/D2930
