metomi/rose#165: rose suite-run log.DATETIME.

Create log directories as log.DATETIME.
Name the current log directory.
Tar-gzip old log directories.
Remove automatic rotation.
Option to housekeep old log directories.
beginnings of #86
working version with meta switch hard coded.

Debug code still present.
Updated documentation.
Added message for when no metadata is found for a file.
tidied up logic.
Will now parse multiple files for metadata

Previously dropped out if one file was missing metadata.
Merge branch 'master' into 165.rose-suite-run.log
training: fixes
training: feedback from @dpmatthews
training: update title
training: brief tour commit
Merge pull request #268 from benfitzpatrick/training.in-depth

Training feedback
training: add cylc broadcast tutorial
add queues
Add queue tutorial
metomi/rose#269: add queue tutorial
Fixes
rose metadata-gen: fix
Merge pull request #271 from benfitzpatrick/metadata-gen.fix

rose metadata-gen: fix