Document how to configure Rose Bush

And improve document on how to configure Rosie.
Doc: rose-install: fix setsid syntax
Merge pull request #993 from matthewrmshin/rose-bush-install

Doc: rose bush install instruction update
rose task-run: fcm_make: fix options confs

The `opts` setting did not work, because it is already used to indicate
optional configuration. This has been changed to `args`.

Fix `opt.jobs` syntax in document.

Add test battery for this built-in app.
Update CHANGES.md
Merge pull request #996 from matthewrmshin/fix.fcm_make.app

rose task-run: fcm_make: fix options confs
Update CHANGES.md
rose bush: cast ws args to str before shlex

It appears that in newer version of cherrypy, query arguments are
encoded in Unicode. Unfortunately, using `shlex.split` on a Unicode
string gives garbage. Casting the arguments into a `str` solves the
problem.
Merge pull request #997 from matthewrmshin/rose-bush-shlex-unicode

rose bush: cast ws args to str before shlex
test-battery: `cylc unregister` where appropriate
Merge pull request #998 from matthewrmshin/t.cylc-unregister

test-battery: `cylc unregister` where appropriate
rose documentation: fix typo
Merge pull request #1001 from benfitzpatrick/doc.fix-rose-task-options

rose documentation: fix typo
Update README.md
Update CHANGES.md
Doc: fix typos
Merge pull request #1002 from matthewrmshin/fix-doc

Doc: fix typos
rose.config_processors.file: ~ expansion in source
Update CHANGES.md and rose-version.js for release
t/rose-suite-scan: fix null config skip logic