CI: test against Ruby 2.1.4
Made Utils::PathPrefix#join to accepts multiple arguments
Set version to 0.3.1.dev so Lotus::Assets can depend on a preview
Implement Utils::Hash#deep_dup
PathPrefix: #join and #relative_join to return a new instance of that class. Made #relative_join to be aware of the previous occurrences of separator
PathPrefix: remove trailing occurrences of separator
PathPrefix: implement relativness and absolutness
Fixing test for JRuby. Thanks to @enebo

Ref jruby/jruby#2053
Merge pull request #39 from janko-m/relativeness-absoluteness

PathPrefix: implement relativness and absolutness
PathPrefix cleanup per #39
Introducing Utils::Deprecation. Closes #35
Simplify test for Utils::IO.silence_warnings
Fix CI for Utils::Deprecation on JRuby
Introducing Utils.jruby? as VM instrospection facility
Merge branch 'master' into simplify-io-test
Merge pull request #40 from lotus/simplify-io-test

Simplify IO test
Fix rbx builds on Travis
See travis-ci/travis-ci#2821
Remove rbx from CI allowed failures
Merge branch 'master' into rbx-2-3-0
Implement Utils::Deprecation for Rbx