Apply level zero (no section) defaults for suite.rc.

For suite definitions we do not load all default values at once, in
order to leave a sparse runtime structure for efficient inheritance.
However, in loading defaults for everything but [runtime] I had
neglected to load the top level non-section defaults (just title and
description).
Fixed reload of async tasks in mixed suites, and sequential tasks.
Site config host matching by regex, not ordered.
Use OrderedDict everywhere to maintain order of parsed config items.

And don't use where not necessary, in the config file spec modules.
Documented site config host matching.
Host matching doc update.
Merge pull request #637 from hjoliver/fix-two-reload-bugs

Fixed reload of async tasks in mixed suites, and sequential tasks.
cylc/cylc#602: gcylc: add ungrouped usercfg
fix oops in previous commit.
.gitignore: add site configuration related entries
Merge pull request #636 from hjoliver/suiterc-level0-defaults

Apply level zero (no section) defaults for suite.rc.
Merge pull request #641 from matthewrmshin/fix-gitignore

.gitignore: add site configuration related entries
Add missing method to Daily cylcing module. Closes #639.

Also fixes another bug: daily step size reported in days not hours.
Other cycling modules checked as ok.
Merge pull request #640 from benfitzpatrick/gcylc.user-rc-ungroup

#602: gcylc: add ungrouped usercfg
Merge branch 'master' into 212.site-host-pattern

Conflicts:
	lib/cylc/cfgspec/suite_spec.py
Unbreak "[viz]collapsed families" for initial gcylc graph view.

Broken by the previous merge.
Merge pull request #643 from hjoliver/gcylc-viz-collapsed-families

Unbreak "[viz]collapsed families" for initial gcylc graph view.
Only write *.processed file for suite.rc

Fix: `gcylc` does not start if user does not have permission to write to
`$CYLC_HOME/conf/gcylcrc/themes.rc.processed`.
Merge pull request #644 from matthewrmshin/fix-gcylcrc-themes.rc.processed

Only write *.processed file for suite.rc
parsec.fileparse: fix double quote

Fix incorrect pattern for matching double quotes.