Enable ESGF query/download

Add the ability to query ESFG and download dataset.
Add MyProxyClient code in modules/thirdparty

Include this source in tree until the superbuild is
ready.
Add python script to launch celery
Clean up if comparision
Add ability to toggle layers
Fix problems introduced by rebase
Add lineSource.js to web/lib/geoweb.min.js
Remove unused file (modules/esgf/down.py)
Add MyProxyClient to path for geoweb
Use OpenID identifer to extract server name

The user needs to enter full OpenID identifier so
the server name can be extracted and passed to
MyProxyClient to authenticate with the correct
server.
Use enter/return key press to dismiss login dialog
Merge remote-tracking branch 'origin/8-esgf-query'

* origin/8-esgf-query:
  Use enter/return key press to dismiss login dialog
  Use OpenID identifer to extract server name
  Add MyProxyClient to path for geoweb
  Remove unused file (modules/esgf/down.py)
  Add lineSource.js to web/lib/geoweb.min.js
  Fix problems introduced by rebase
  Add ability to toggle layers
  Clean up if comparision
  Add python script to launch celery
  Add MyProxyClient code in modules/thirdparty
  Enable ESGF query/download