update README.md
fix spec/spec_helper.rb
bump version to 0.1.0
add platform to musk.gemspec
install pry-nav
replace dev dependencies with dev group in Gemfile
add bundler_args to .travis.yml
bump version to 0.1.1
add required_ruby_version to musk.gemspec
bump version to 0.1.2
release 0.1.2