This commit includes an 'apt-get update' call before any 'apt-get
install' command. This way the packages database is always ready,
even if no bootstrap procedure has been executed.
With this commit package manager are always set to include only
required packages or set to include required and recommended
packages.
This commit fixes#285
The request_package_lock was renamed into request_package_exclusion
because that is the goal, to actually exclude(skip) a package. From
an implementation point of view this is done to set a lock in the
zypper case. However other package managers might do it differently.
The interface should stay consistent with regards to the user goal
and not with the package manager specific implementation. This
Fixes#248
Zypper supports the al (add lock) command which allows to ignore
a package in the dependecny resolution process. This is useful
to prevent installation of a package which was pulled in by e.g
a recommendation flag from the spec file. Packages marked to be
ignored are not handled for apt and yum right now. Using this
feature together with an unsupported package manager backend
results in a warning to the user
