rose_prune: user interface refresh.

Functionalities now divided into 4 settings:
* prune-remote-logs-at=cycle ...
* archive-logs-at=cycle ...
* prune-work-at=cycle[:globs] ...
* prune-datac-at=cycle[:globs] ...

The 1st two functionalities call the underlying libraries of `rose
suite-log` to re-sync the remote job logs, prune them from the remote
hosts, (and archive the cycle job logs).

The last two functionalities are to prune items in the work directories
and the share cycle data directories. Globs can be specified for each
cycle so that only matched items in the relevant directories are
pruned.
t: rose_prune: now passes reliably.

Ordering of JSON files and dot files were making things unreliable
previously.
Merge branch 'master' into rose_prune
rose_prune documentation: fix typos.
Merge pull request #789 from matthewrmshin/rose_prune

rose_prune: user interface refresh.