vyatta-cfg-vpn: move scripts/vtiIntf.pm to lib/Vyatta/VPN/vtiIntf.pm

Move vtiIntf.pm to a more logical place, in line with all the other
packages.
vyatta-cfg-vpn: update parseVtiTun to account for vti changes

Update the parseVtiTun function to account for the new way of
configuring VTIs.

Bug #358 http://bugzilla.vyos.net/show_bug.cgi?id=358
vyatta-cfg-vpn: update vti creation in line with changes to strongswan

Update the VTI creation process to go along with the changes added to
the vyatta-strongswan package, due to changes in the kernel vti module.

This also removes the need for additional netfilter rules to ensure that
packets are directed to the corresponding VTI.

Bug #358 http://bugzilla.vyos.net/show_bug.cgi?id=358
vyatta-cfg-vpn: reduce the vti mark base to prevent integer overflow

Reduce the vtiMarkBase value to prevent integer overflow on the created
ip xfrm states and policies.
vyatta-cfg-vpn: formatting changes for style consistency

Update lib/Vyatta/VPN/vtiIntf.pm to have consistent identation levels
and style throughout.
vyatta-cfg-vpn: remove the cfgvti helper program

The cfgvti helper program was originally added for configuring VTIs.
The functionality it provided is now included upstream in iproute, so
it is no longer required following the previous commits for Bug #358.

Bug #358 http://bugzilla.vyos.net/show_bug.cgi?id=358
0.12.105+vyos1+helium6