Merge pull request #4 from cylc/master

Bring my copy up to date
Remove -J flag from qstat calls

The -J flag is not neccessary to view job status information, and for
OpenPBS systems will cause an error
Merge pull request #543 from ScottWales/qstat

Remove -J from qstat polling
job file: send error from namerslv to /dev/null

Stop output of "/etc/resolv.conf does not exist".
Visualization settings override cylc-graph.
Merge pull request #546 from matthewrmshin/namerslv

job file: send error from namerslv to /dev/null
Tidier grouping logic.
Merge pull request #544 from arjclark/cylc-graph-fix-visualisation

cylc graph: use visualization settings
Removed old CLI switch reference.
Merge pull request #550 from arjclark/doc-tidy

removed old cylc gui CLI switch reference