Polished exception handling when importing extensions: - Warning about failed import is printed on one line. - For this warning the [extensions] section key is used, because the value doesn't have to be set. - Whan a --traceback is requested, exit immediately to not mix up problems when importing an extension with other problems.

#!/bin/sh
#
mkdir t
cd t
hg init
echo 0 > a
echo 0 > b
hg ci -A -m m -d "1000000 0"
touch nottracked
hg locate a
hg locate NONEXISTENT
hg locate
hg rm a
hg ci -m m -d "1000000 0"
hg locate a
hg locate NONEXISTENT
hg locate
hg locate -r 0 a
hg locate -r 0 NONEXISTENT
hg locate -r 0