[#531] Update data viewer docs for CKAN 2.0
Merge remote-tracking branch 'origin/master' into 531-data-viewer-docs
[#531] Update data viewer docs
[#531] Add note about /preview URL for resources.
Merge branch 'master' into 531-data-viewer-docs

Conflicts:
	doc/configuration.rst
[#531] Fix references after merge
Merge pull request #531 from okfn/531-data-viewer-docs

Update Data Viewer docs for 2.0