- Copy stable/10@296371 to releng/10.3 in preparation for 10.3-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.3.
- Update default pkg(8) configuration to use the quarterly branch.

Approved by: re (implicit)

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Rename the trunk(4) driver to lagg(4) as it is too similar to vlan trunking.

The name trunk is misused as the networking term trunk means carrying multiple
VLANs over a single connection. The IEEE standard for link aggregation (802.3
section 3) does not talk about 'trunk' at all while it is used throughout IEEE
802.1Q in describing vlans.

The lagg(4) driver provides link aggregation, failover and fault tolerance.

Discussed on: current@