Error handling in links_group_html

git-svn-id: https://svn.eionet.europa.eu/repositories/Naaya/trunk/eggs/naaya.chm@19779 a0171fae-0946-0410-966d-b1775066cd26
Released 3.0.16, new version 3.0.17

git-svn-id: https://svn.eionet.europa.eu/repositories/Naaya/trunk/eggs/naaya.chm@19780 a0171fae-0946-0410-966d-b1775066cd26
Reverted some unwanted changes

git-svn-id: https://svn.eionet.europa.eu/repositories/Naaya/trunk/eggs/naaya.chm@19781 a0171fae-0946-0410-966d-b1775066cd26