Removed obsolete and currently unused proposals

The code using this was deleted in commits 5a2a8db and cf6260a
Fixed proposal when virtual machine pattern is selected. bnc#884517
Cleanup - dropped unneccessary imports from Lan module
Updated changelog
Updated documentation.
Merge pull request #221 from mchf/bnc884517-invalid-hostname

Fixed incorrect proposal when virtual machine pattern is selected
Enabled Add button in Overview during installation. bnc#889359
Updated changelog