strongswan: Update to 5.0.3rc1.
strongswan: Update to 5.0.3.
Add strongswan update to core update 68.
ipsec: Set IKE/IPsec lifetime to strongswan defaults.

As suggested by Tom Rymes:
https://bugzilla.ipfire.org/show_bug.cgi?id=10346
Merge branch 'strongswan-next' into next