pmrule: make backup file test more robust

This prevents an exception in the event backup entries are not in the
correct format and brings the test in line with alpm's backup parsing
which splits on the last tab rather than the first.

Signed-off-by: Andrew Gregory <andrew.gregory.8@gmail.com>
pmtest: allow tests to specify db version

Signed-off-by: Andrew Gregory <andrew.gregory.8@gmail.com>
pacman: add --confirm option

--confirm cancels the effect of a previous --noconfirm.  This makes it
easier for scripts to default to --noconfirm but allowing users to
override it.

Signed-off-by: Andrew Gregory <andrew.gregory.8@gmail.com>
pmtest: allow tests to specify test binary

* add cmd property to test cases (defaults to pacman)
* allow specifying path directories for test command

The ability to manually specify a particular binary is preserved in
order to allow running individual tests with differently named binaries
such as lt-pacman.

Signed-off-by: Andrew Gregory <andrew.gregory.8@gmail.com>
add pacman-db-upgrade test

Signed-off-by: Andrew Gregory <andrew.gregory.8@gmail.com>