Corrections based on forum threads. Dutch translation 04-01-2013

git-svn-id: https://dev.virtuemart.net/svn/virtuemart/trunk/virtuemart@6799 87cc427b-4a1e-0410-b729-b2260ec0f063
Corrections based on missing ". Dutch translation 04-01-2013

git-svn-id: https://dev.virtuemart.net/svn/virtuemart/trunk/virtuemart@6800 87cc427b-4a1e-0410-b729-b2260ec0f063