Initial rubocop support.

Per the mailing list thread, introducing Rubocop as a replacement for Tailor.
Assuming Jenkins likes this, more pedantic patches will follow to make Rubocop
happy.

rubocop              | 24 files inspected, 1617 offences detected

Change-Id: I10077146fbaa015c4b74cac826761de273c5639d
Rubocop testing of the attributes and testing documentation.

The Testing section of the README.md was broken out into the new TESTING.md to
explain how the cookbook is being tested. Rubocop is testing the attributes/
files and the .rubocop.yml has documented excluded rules.

Change-Id: I0a5f4124a061617779425490d198c00d931c4cc1
Rubocop support for metadata.rb and Gemfile

Replace double-quotes with single-quotes for now, expect this to act as a gate
in the future.

Change-Id: I10ff8b23517cb334905b162ce14059dbf23d7bc8
Remove default recipe from block-storage

There is no default that makes sense for this cookbook, so remove the empty
recipe.

Change-Id: I76a714f207e7b96a093f4f1c0c92535d85efbc9e
Merge "Initial rubocop support."
Merge "Rubocop testing of the attributes and testing documentation."
Merge "Rubocop support for metadata.rb and Gemfile"