Halfway through first whack at "Adding entries to the blog"

…which can be found [here](http://objectsonrails.com/#sec-5_6).  Note that so far this branch is a straight-up adaptation of the Objects on Rails working example; there are three more (simple) tasks in this section ("Using ActiveModel", "The Post creation action", and "Making the Blog object into a Singleton") that I intend to adapt *before* creating Mutators for the new (since we branched off the `Mutators` branch itself) controller actions. Once I have *those*, we can merge (squash?) this back into the `Mutators` branch, start looking at bringing another candidate up to that point.

RSpec: 46 examples, 0 failures
Script: 0 tests: 0 failures, 0 errors, 0 pending, 0 omitted
RuboCop: 19 files inspected, no offenses detected
RuboCop global overrides in `.rubocop.yml`: 4
Finished 'Adding entries to the blog'.

A comedy of errors compounded by ten hours of network/routing problems.

The main event: the main blog index view now displays blog posts (though in a real app, styling would be cleaned up and Bootstrapped).

This completes the [*Adding Entries to the Blog* page](http://objectsonrails.com/#sec-5_6), page 16 in the online book, pp. 34-37 in the print or ebook).

RSpec: 48 examples, 0 failures
Script: 0 tests: 0 failures, 0 errors, 0 pending, 0 omitted
RuboCop: 19 files inspected, no offenses detected
RuboCop global overrides in `.rubocop.yml`: 4