tests: fix style issue of importing hgweb in embedded code fragments
Some test scripts are excluded in test-check-module-imports.t, because
import-checker.py reports that hgweb and/or hgwebdir of
mercurial.hgweb are not imported in recommended style.
To fix this issues, this patch make python code fragments embedded in
these files import hgweb from mercurial package at first, and refer
hgweb and hgwebdir via imported hgweb.
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install::
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing::
$ make local # build for inplace usage
$ ./hg --version # should show the latest version
See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.