First swing at converting from racoon to StrongSWAN.
It allows to use existing configurations on xml to generate StrongSWAN configurations.
So its only IKEv1

* Missing support for dynamic ips(hostnames)
  - resolver plugin of StrongSWAN needs to be configured in strongswan.conf
* Authentication plugin with pfSense authentication framework
  - New plugin almost completed

* More testing hence this being pushed now to have more broader look

TODO
* Integrate IKEv2
* Move dynamic IP allocation to an SQLite backend
* Provide more options in authenticating as a client(initiator)
* Restrict interfaces where StrongSWAN listens for incoming connections to only those configured

FUTUTE
* Move all configuration to SQLite backend
* Integrate more authentication scenarios of IKEv2
Remove PBI scripts since it'll be installed dynamically by tools
Fix test, allows restoring last backup in the list. Fixes #3438
Standardise LAN net display

On the main firewall rules multi-rule display it shows "LAN net" "WAN net" etc. But on the edit screen it shows "LAN subnet" "WAN subnet" etc. Make the edit screen have the same text as the main screen - this has ben a source of enough little questions/queries on the forum.
Standardise LAN net display
Standardise LAN net display
Merge pull request #902 from phil-davis/master

Standardise LAN net display
Add support for signed PBI, help ticket #3365:

- Add an option to allow user to accept unsigned packages
- The only missing part is public key, that needs to be added to
/var/db/pbi/keys/pfSense.ssl
s/http/https/ for doc.pfsense.org
Remove this sort. It's unnecessary and causes problems when editing and saving privileges, it can reorder users and cause edits to the wrong account.
Add specific permission for easyrule.