tests/test-revlog-group-emptyiter

merge: introduce tool.check parameter

tool.check is a list of check options, and can be used in place of
tool.checkchanged and tool.checkconflicts:

Equivalences:
tool.checkchanged = yes
tool.checkconflicts = no
tool.check = changed

tool.checkchanged = no
tool.checkconflicts = yes
tool.check = conflicts

tool.checkchanged = yes
tool.checkconflicts = yes
tool.check = changed, conflicts

Add _toollist() wrapper for ui.configlist() to implement this consistently.

checkchanged and checkconflicts are still supported, but check is
preferred for implementing new check options.

#! /bin/sh

# issue 1678

echo "# -- setting up base repo"
hg init a
cd a
touch a
hg ci -Am a
cd ..

echo "# -- cloning base repo"
hg clone a b
cd b

echo "# -- setting up cset to push"
hg up null
touch a
hg ci -Am b # different msg so we get a clog new entry

echo "# -- pushing"
hg push -f ../a