some paludis fixes

- only search for non-masked packages
- increased the command timeout for the installation process to a reasonable large number
fixed paludis package provider manifest
use package.timeout for the cave timeout value
moved init of timeout for paludis packages to the right place
whitespace fix in paludis_package.rb
Merge pull request #1680 from BundesIT/master

Some minor fixes for the Paludis package provider