Update gemspec config.

- Include homepage
- Lock into Ruby 2.x

  Ruby 1.8.7 and 1.9.2 have already reached end-of-life. EOL for 1.9.3
  is just around the corner:

  https://www.ruby-lang.org/en/news/2014/01/10/ruby-1-9-3-will-end-on-2015/

  Marking this as 2.x for now will give the most flexibility in
  available APIs and features to use.
- Move to explicitly defining which files are executables. This allows
  other development related binstubs to be used without issue.
Lighten spec_helper

With RSpec 3.x the goal is to keep the `spec/spec_helper.rb` as light as
possible. This allows for faster isolated testing.

Removing the auto-require statement means specs only need to load what
they use. This also helps developers learn about various support helper
files.

The other remaining settings only were used by a single spec file. Move
those into it.
Tweak library requires for specs.

The `rouge` gem has a lot of warnings it generates. Making it difficult
to isolate warnings coming from our lib. Load `rouge` first so we can
safely ignore it's warnings.

Require our lib after configuring RSpec exposing our own warnings.
Fix reported Ruby warnings.
Switch to autoloading.

Keeps gem loading light weight and fast. Only those classes used by the
requiring lib/app will get loaded when needed.
Minor update to prevent text box scrolling.
Remove the default org.

We shouldn't default to our org with a public gem. Keeping the branch
defaulting to "master" makes sense, since this is a very common branch
name.
Allow the environment to dictate repo defaults.
Ignore bundler --standalone files.
Move debug related gems out of gemspec.

When doing development, running `bundle install` will take into account
the Gemfile. By default the Gemfile references the gemspec so everything
appears to come from the gemspec alone. We are free to add more
dependencies to the Gemfile as we see fit.

Gems added directly to the Gemfile will **not** be included in the
dependencies list when the gem is built.
Include travis build configuration.
Merge pull request #1 from RadiusNetworks/minor-gem-related-updates

Minor gem related updates