Add multi-protocol support (tcp and udp at once)

This patch changes how 'etc_services' role configures protocols for
a service. By default, if no protocols are specified, both tcp and udp
protocol entries will be created. You can specify protocols to generate
using new 'item.protocols' list in a service definition.

You can still use 'item.protocol' key in service definitions, but this
should be considered as legacy and avoided, this syntax will be removed
in the future.
Merge pull request #1 from drybjed/upgrades

Add multi-protocol support (tcp and udp at once)