Added VPN IPSec connection-type recommendation for the close-action and
dpd settings.
For example close-action restart should not be added on both peers
The command to set the vpn interface is changed in the rolling release
which is not modified in many configuration examples, corrected syntax
in all pages where it is mentioned
Removed the note from the firewall page as nat grouping is not added yet
Added the information about new option 'none' in the site-to-site ipsec vpn
page
There were minimal grammatical and spelling mistakes in the files which I
corrected as documentation proof reading.
Also added information about few ipsec vpn parameters.