Plugin for toggling visibility on cluster deploy

We need to show/hide certain parts of barclamp configuration only when a
cluster is deployed. This jQuery plugin adds that functionality.

Example usage:

<fieldset data-elements-path="database-server" data-show-for-clusters-only="true">

This element (and its children) will be shown only when:

1. A cluster is already part of a deployment
2. A cluster is dragged into the node list

The data-elements-path specifies where to check in the deployment JSON
for already deployed clusters. data-show-for-clusters-only enables this
plugin for a given element.

(cherry picked from commit 1b710e3121128237ac555e385a23534113d421d3)
Add huge fixme

(cherry picked from commit 8fefb64e8caac78b833336cb85f1235701786cad)
Initialize cluster conf plugin in application.js

(cherry picked from commit 0043307898a81d18069a1f815766ae73ddb8ef9f)
isCluster matches on ":" instead of "cluster:"

as suggested by @tboerger

(cherry picked from commit 3910c003a81fdad361c039b34bd02d9ae17ef3b4)
Add helper for finding unclaimed drives

This is a prereq for cinder to check if any disk-backed volume can be
created.

(cherry picked from commit aa37d48140d46466634eaa40ec4573e54b3af1af)
Handle removed node referenced by another proposal

When another proposal removes a node which the current proposal
references, the corresponding DOM element is no longer available in the
deployment list. However, info from this element is needed by the
nodeList, when it triggers an event that a node has been removed.

Make the nodeList look up the info in some other way.

(cherry picked from commit cd7be03a17cb2b77140003438db1544d65ef01f0)
webui: Sort clusters in the list of clusters

(cherry picked from commit 284af51b72cdf0ee8789d552f12547602621ee6c)
Merge pull request #1009 from vuntz/roxy-sync

Sync with roxy