site/plugins: update the plugins list
site/plugins: update the plugins list

The plugins now are hosted in a new organization [Weaveworks Plugins]
(https://github.com/weaveworks-plugins).
This patch updates the list of the available plugins and their links to the new
repositories.

alban/scope,paulbellamy/scope,weaveworks/scope,weaveworks/scope,alban/scope,kinvolk/scope,weaveworks/scope,alban/scope,paulbellamy/scope,kinvolk/scope,weaveworks/scope,kinvolk/scope,paulbellamy/scope,paulbellamy/scope,weaveworks/scope,alban/scope,weaveworks/scope,kinvolk/scope,alban/scope,paulbellamy/scope,kinvolk/scope,kinvolk/scope,alban/scope,paulbellamy/scope