docstring fix

The docstring of class Extended_availability_zone was totally same as
Extended_server_attributes. This patch improves this docstring.

Change-Id: Ifd59d8dd149975c7f2653a0e0effadfc88d119d4
Fix string formatting of exception.NoUniqueMatch message

There is no implicit logger string formatting happening, so
we need to do this on our own.

Change-Id: I13dfb804d55b5ede2987e355f8a932f237b56c56
Remove vi modelines

We don't need to have the vi modelines in each source file,
it can be set in a user's vimrc if required.

Also a check is added to hacking to detect if they are re-added.

Change-Id: I347307a5145b2760c69085b6ca850d6a9137ffc6
Closes-Bug: #1229324
Merge "Fix string formatting of exception.NoUniqueMatch message"
Merge "docstring fix"
Merge "Remove vi modelines"
Merge commit 'refs/changes/61/58861/12' of git://gold.eng.hq.xensource.com/git/github/openstack/nova into tmpbranch
Merge commit 'refs/changes/53/60253/8' of git://gold.eng.hq.xensource.com/git/github/openstack/nova into tmpbranch

Conflicts:
	nova/virt/xenapi/vm_utils.py
Merge commit 'refs/changes/08/60808/6' of git://gold.eng.hq.xensource.com/git/github/openstack/nova into tmpbranch
Merge commit 'refs/changes/97/66597/4' of git://gold.eng.hq.xensource.com/git/github/openstack/nova into tmpbranch
Merge commit 'refs/changes/79/69879/3' of git://gold.eng.hq.xensource.com/git/github/openstack/nova into tmpbranch