checkapidoc: improve detection of imported symbols (support `from x import y as z`)
checkapidoc: improve detection of imported symbols (support `from x import y as z`)

git-svn-id: eda3d06fcef731589ace1b284159cead3416df9b@11267 af82e41b-90c4-0310-8c96-b1721e28e2e2

walty8/trac,walty8/trac,jun66j5/trac-ja,walty8/trac,jun66j5/trac-ja,jun66j5/trac-ja,jun66j5/trac-ja,walty8/trac