Cosmetic rewording of spec description.

Cautiously re-trying failed Big Bang as iteration, Step 1 of *n*.

RSpec: 590 examples, 0 failures
RuboCop: 140 files inspected, no offenses detected
First whack at "member can publish article/view on landing page" spec.

Cautiously re-trying failed Big Bang as iteration, Step 2 of *n*.

Note the use of `expected` and `old_expected` in that feature spec
(lines 21-28). `old_expected` is the every-time-the-same-content output
from `FeatureSpecNewPostHelper#create_image_post` (and
the functionally similar `#create_text_post`); `expected` will match the
new, sequenced output to be added in the next commit.

RSpec: 618 examples, 0 failures
RuboCop: 144 files inspected, no offenses detected
FeatureSpecNewPostHelper now uses PostCreatorData as data source.

Cautiously re-trying failed Big Bang as iteration, Step 3 of *n*.

This got the "member can publish article/view on landing page" spec to
where it should have been 24 hours ago, eliminating the old, always-
identical data generated for post title and body and replacing it with
sequences.

Why not do this with FactoryGirl? I'd never used it with feature specs
on any earlier project and, frankly, it didn't even cross my mind until
just now. But that *would* eliminate the need for the `PostCreatorData`
support class entirely.

RSpec: 618 examples, 0 failures
RuboCop: 144 files inspected, no offenses detected
Member can now publish multiple distinct articles, with helper.

Cautiously re-trying failed Big Bang as iteration, Step 4 of 4.

FeatureSpecNewPostHelper class can now be used to publish multiple posts
which each have unique content matching a common pattern. This gets us
where the "big bang" from the abandoned breadcrumb would have gotten us
had it succeeded. Yak shave complete!

RSpec: 622 examples, 0 failures
RuboCop: 144 files inspected, no offenses detected