tests: enable import checker for all **.py files
Several known-bad files are excluded as they couldn't be trivially fixed.
That's the same as
99a2bdad0fda.
--- a/tests/test-check-module-imports.t Sat May 14 14:33:45 2016 +0900
+++ b/tests/test-check-module-imports.t Sat May 14 14:16:43 2016 +0900
@@ -155,8 +155,12 @@
Known-bad files are excluded by -X as some of them would produce unstable
outputs, which should be fixed later.
- $ hg locate 'mercurial/**.py' 'hgext/**.py' 'tests/**.py' \
+ $ hg locate '**.py' \
> 'tests/**.t' \
+ > -X contrib/debugshell.py \
+ > -X contrib/win32/hgwebdir_wsgi.py \
+ > -X doc/gendoc.py \
+ > -X doc/hgmanpage.py \
> -X tests/test-hgweb-auth.py \
> -X tests/hypothesishelpers.py \
> -X tests/test-ctxmanager.py \