NetEventDatagrid customisation

[Apfelwurm]

There is some customisation missing in the current NetEventDatagrid

Missing localisation:

• Netevent datagrid pagination Rows per page:
• Netevent datagrid Edit dialog title and buttons
• Netevent datagrid "settings" button Columns text
• Netevent datagrid Add dialog title and buttons

Other stuff:

• The add feature seems to just open the edit dialog