SNI macher for HTTPtables

[krizhanovsky]

Scope

Need to be able to match SNI against HTTPtables rules, just like Host header.

Testing

Add a functional test for HTTPtables to match SNI, e.g. different Host and SNI values must be tested.

[krizhanovsky]

Basically there is nothing to do with SNI in HTTPtables rules and #1608 requires strict matching between vhosts and certificates, so vhost rules are enough.