[config] Add config for package manager

Signed-off-by: Matti Kosola <matti.kosola@jollamobile.com>
[tester] Add option to use pkcon instead of zypper

Signed-off-by: Matti Kosola <matti.kosola@jollamobile.com>
Merge pull request #3 from mkosola/master

Use pkcon instead of zypper for installing test packages