Rules version 0.6.0 updated changelog

Bump version to 0.5.2

Bump version to 0.5.1

Adding makefile for auto-generating PDF (bazelruby#106)

* Adding  makefile for auto-generating PDF

* Updating adoc

Pretty-up README

Version vandidate 0.4.0 — upgrade Rubies + Setup (bazelruby#77)

## RulesRuby Version 0.4.0 Candiate Merge:

* Updating .bazelrc
* Moving rbenv install to bin/setup + .travis.yml
* Fixing buildifier complaints
* Fixed TravisCI errors
* Comment out failing test with Docker
* Upgrade various top-level dependencies to the latest
* Upgrade Bazel to 3.4.1
* Really switch to Ruby 2.7.1 as the default

Adding CHANGELOG and VERSION.yml file. Bump version to 0.3.0

Merge pull request bazelruby#56 from bazelruby/kig/fix-ruby-version-d…

…etection

Fixing brittle Host Ruby version detection.

Updating remote sources