docs: add a few missing glossary definitions

Change-Id: I2fe4c79c8da760837c9f4599a8772c22aec105c6
docs: describe notify cc, give extra hints about shared administration

Change-Id: I29a663a8b50cdc647a6da7879bc3fca625a05c7b
recipes with <hostRequires force=""/> are not virtualisable

Bug: 1136144
Change-Id: I4e2866dc80fbda0ec58fe821a5277b103a703497
remove hardcoded product names in beaker-import

The individual .treeinfo importers now look at the structure of the
config, rather than the product name, to decide whether they can handle
it or not.

There are actually still hardcoded references to RHEL4 and earlier
(which I don't care enough about to fix) and Fedora (which is difficult
to fix without changing repoids which might be an annoying compatibility
break).

But the key point is that RHEL5-style .treeinfo files (as used by CentOS
and Fedora) can now be imported regardless of the product name.

This patch also adds test coverage for CentOS and RHS, and fixes issues
with the main repo not being imported properly on CentOS and
RHEL7 pre-GA.

Bug: 1070575
Change-Id: Ie60c8728c9c64bc338538cf5d0e3b515a09cd505
docs: describe WATCHDOG_SCRIPT

Bug: 1129020
Change-Id: I4a39f0d857d4ba810af23b62f67dd847c3e5996f
docs: XMLRPC API docs for jobs.set_response

Bug: 1127509
Change-Id: I26d5e834115e3c0cde0b1a07a3ab3035c9462bb0
docs: expand description of recipe set ack/nak

Bug: 1127509
Change-Id: I4bc3e507fa48e0e4839eff896fe0a238104c60ec
use OSMajor.default_install_options for VirtResource and GuestResource

Bug: 1138533
Change-Id: Id2eb4226d8c6289331592fbeab9b540d618d5912
use OSMajor custom install options for VirtResource and GuestResource

Bug: 1139951
Change-Id: Ibd6fd95cfc2e62c584ecbe09c2f36b2fea86852d
add bz950903 to 0.18.0 release notes

This was accidentally omitted since the patches didn't have
a documentation/whats-new/next/* file and the Bugzilla milestone was not
set correctly.

Change-Id: I0fbcd6de338572d4c85f89f2cf0f10979531832d
release notes for 0.18.1

Change-Id: Ic7dc1c63869ca2db9e72eee44172694015d8192c
Automatic commit of release 0.18.1