Updated README. No changes to code.
FeatureSpecLoginHelper updated; UserEntity cleaned

UserCreatorData now internal to LoginHelper (as that's the only class
that would use it now), and LoginHelper takes a hash of attribute
values.

UserEntity specs now brought up to RSpec 3, using standard
`described_class` rather than home-baked `klass`.

RSpec: 710 examples, 0 failures
RuboCop: 178 files inspected, no offenses detected
Feature specs exercising user name validation.

RSpec: 714 examples, 0 failures
RuboCop: 179 files inspected, no offenses detected
Ripping out no-longer-needed code. Again.

RSpec: 714 examples, 0 failures
RuboCop: 178 files inspected, no offenses detected
More cleanup.

`UserRepository#find_by_name` was really used only in one place, that
itself was part of a larger class that wasn't being used. Whatever I'd
intended `UserDataValidator` for, I'm not using it now and I've
forgotten the original reason. So out it goes.

RSpec: 674 examples, 0 failures
RuboCop: 170 files inspected, no offenses detected
Added "member create valid text post" feature spec

Also *commented out* any mention of `RepositoryBase#delete`; not used
now, but will almost certainly be used by future admin interface.

Minor additional cleanup.

RSpec: 672 examples, 0 failures
RuboCop: 171 files inspected, no offenses detected
New feature spec hits Actions::NewUser failure.

I'll wake up sometime before Halley's Comet returns…

RSpec: 673 examples, 0 failures
RuboCop: 172 files inspected, no offenses detected
Added view-nonexistent-user feature spec.

People *do* key stuff in, and people *do* make typos. We now prove that
we recover reasonably gracefully.

RSpec: 675 examples, 0 failures
RuboCop: 173 files inspected, no offenses detected
Added login-as-nonexistent-user feature spec.

RSpec: 677 examples, 0 failures
RuboCop: 174 files inspected, no offenses detected
User profile cannot be updated with invalid data.

Proven by an all-new feature spec that drove some important changes in
`Actions::UpdateUser`.

RSpec: 679 examples, 0 failures
RuboCop: 175 files inspected, no offenses detected
EditPost action now checks for invalid slug.

Cleaning up loose ends. Spec coverage now 100%.

RSpec: 681 examples, 0 failures
RuboCop: 175 files inspected, no offenses detected
UpdatePost action now checks for invalid slug.

Cleaning up loose ends. Spec coverage now 100%.

RSpec: 683 examples, 0 failures
RuboCop: 175 files inspected, no offenses detected
Cleaning up entity-validation ambiguity.

More loose ends. Entities are limited in the amount of validation they
can realistically do without access to the database.

RSpec: 683 examples, 0 failures
RuboCop: 175 files inspected, no offenses detected
More minor cleanup.

Dummy entities never had their #name/#author_name methods called, and
shouldn't in future.

RSpec: 683 examples, 0 failures
RuboCop: 175 files inspected, no offenses detected
Added "same user name twice fails" feature spec.

RSpec: 686 examples, 0 failures
RuboCop: 176 files inspected, no offenses detected
New invalid post-update feature spec.

Also changes to Actions::UpdateAction, so that error condition *always*
sends back JSON-encoded error data.

RSpec: 687 examples, 0 failures
RuboCop: 177 files inspected, no offenses detected
Merge pull request #134 from jdickey/issue-120

Harmonising feature spec coverage of code per Issue #120. Reaching the point of diminishing returns?

RSpec: 687 examples, 0 failures
RuboCop: 177 files inspected, no offenses detected