- Copy stable/10@285827 to releng/10.2 in preparation for 10.2-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.2.
- Update default pkg(8) configuration to use the quarterly branch.[1]

Discussed with: re, portmgr [1]
Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r274496:

Fix mdoc warning by removing empty lines.

Sponsored by: The FreeBSD Foundation

MFC r272294 by gavin@:

Make clear in the ipheth(4) hardware notes that this driver is for the
tethering functionality only. Add a "bugs" section to give a pointer
to usbconfig set_config if the device isn't automatically detected.

MFC r272106 by gavin@:

Add basic man page for ipheth(4).

Add basic man page for ipheth(4).

MFC after: 1 week