Merge pull request #922 from N0YB/RELENG_2_1

XHTML Compliance
Help ticket #3449:

Improve data validation to avoid save a host/subnet or a IPv4 with
invalid mask. The reported error is on javascript and only happen on
IE8,but this fix will prevent the same issue happening in the future on
a different browser.
XHMTL Compliance

IPsec Status Tabs
Mostly element closings and minimizations (nowrap), empty table row.