setup.py: Add 'mercurial' as include dir for the inotify compiler.
This patch adds access to util.h for the inotify C module by adding the
"mercurial" directory as an include dir, enabling access to the macros defined
in util.h.
#!/bin/sh
# Testing that hghave does not crash when checking features
"$TESTDIR/hghave" --test-features 2>/dev/null