Added route for `users#index`.

Next up; a controller method for it.

Pinging Issue #65.

RSpec: 571 examples, 0 failures
RuboCop: 139 files inspected, no offenses detected
New UsersController#index action using DUMMY VIEW.

And related view, and policy (authorisation) class.

Also:
* Fixed longstanding crap code in decorators/views where views
explicitly decorated incoming objects (which they shouldn't ever have
to do);
More progress on user index view.

We've

* Updated `UsersController#index` to get the authorisation/decoration
ordering right; since the decorator passes through everything it
doesn't define itself, Pundit shouldn't know or care;
* Added an `#authored_by` scope to the `PostData` implementation model;
* Added a `#registered` scope to the `UserData` implementation model,
eliminating the guest user when desired;
* The `views/users/index.slim` template now uses real user data! Woot!
It's still uglier than ugly, but we'll get there!

RSpec: 581 examples, 0 failures
RuboCop: 139 files inspected, no offenses detected
Cleaned up FactoryGirl calls for object lists.

For each of the "strategy" methods FactoryGirl implements, such as
#build, #attributes_for, etc., there is a corresponding method to build
lists of items: #build_list, #attributes_for_list, etc. The
documentation, especially on a quick read, points out `build_list` and
`create_list` without noting that *any* strategy method has such a list
method. This is Useful, allowing us to clean up some code and speed up
specs slightly.

RSpec: 581 examples, 0 failures
RuboCop: 139 files inspected, no offenses detected
Updated navbar/sidebar menus, adding user index.

Also took the opportunity to remove a couple of no-longer-needed
`focus` tags from the BlogController spec.

RSpec: 589 examples, 0 failures
RuboCop: 139 files inspected, no offenses detected
Added "User can view member-list page" spec.

RSpec: 590 examples, 0 failures
RuboCop: 140 files inspected, no offenses detected
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
Guest viewing member list sees no active/current-user highlight.

Starting to wind down Issue #65.

Also fixed a major malfunction with the `FeatureSpecHelperBase` where it
assumed that its data was an instance of `PostCreatorData`. This also
involved creating a new `UserCreatorData` class. We also needed to
change the existing "member can view other member's profile" spec to
change the way user data was generated; what's now in the `#step` method
is no longer automatic.

RSpec: 635 examples, 0 failures
RuboCop: 147 files inspected, no offenses detected
Logged-in member viewing member list sees his entry highlighted.

This should close Issue #65.

Two major new bits of code:

1. New `UserDataDecorator#build_index_row_for(post_count)`; takes all
   the stuff that was being explicitly done in the index view to build a
   user-listing row and moves it in here, so that the row attributes can
   change depending on whether the user being reported on is the current
   user. (Takes five lines of template code down to 2);
2. New `member_viewing_member_list_sees_own_listing_highlighted` feature
   spec. Note the (long) setup block, where it marshals copies of the
   user data into and out of an array. THIS IS THE *ONLY* SAFE WAY TO DO
   A DEEP COPY IN RUBY.

RSpec: 636 examples, 0 failures
RuboCop: 148 files inspected, no offenses detected
Merge pull request #83 from jdickey/issue-65

Closes Issue #65. User profile pages listed and viewable.