Fix graphing test

Allow `cylc graph` to print plain graph to standard output if the output
file argument is a `-`.

Use single `perl` command to parse graphing result, instead of 2 `sed`
and a `perl`.
Fix blank entry being interpreted as 0 offset.
Add test to ensure ongoing behaviour.
Removed some unnecessary graph update code.
Merge pull request #1167 from arjclark/fix_explicit_null_final_cp

cylc config: Fix explicit null final cycle being interpreted as 0 offset
Merge pull request #1168 from hjoliver/graph-cmd.decruft

Removed some unnecessary graph update code.
Fix syntax that will break in new versions of bash
Merge pull request #1165 from matthewrmshin/fix-graphing-test

Fix graphing test
Fix unbounded final-cycle-point sequences.

Sequences based on the final cycle point are created by
counting backwards from it. Sequences that also have a
fixed number of repetitions are bounded and also have
well defined start points. This means that they can be
reversed in the isodatetime library, so that they start
counting from their own start point.

However, sequences based on the final cycle point with
no repetitions specified are unbounded, and don't have
a start point in the isodatetime library. This means that
they generate points counting backwards from their end
point, which is in the wrong order for cylc.

This change generates a start point for these unbounded
final cycle point sequences so that the result is points
in the right order. We can just guess the start point
by iterating back from the end point until we reach
the initial cycle point area.
fix time_parser internal tests
Insert namespace list members to correct position.
Removed obsolete documentation.
Correction to previous.
Added a new test.
Removed unused import.
Removed debug code.
Merge pull request #1170 from benfitzpatrick/fix-recurrence-parse-final-trunc

Fix unbounded final-cycle-point sequences.
Addressed feedback.
Merge pull request #1171 from hjoliver/fix-namespace-list-order

Fix namespace list order
Merge branch 'master' into async-staggered-start-up-fix