Object#inspect must be compatible with default external encoding
CRuby #595 is not fixed yet
CRuby #4869 is not fixed on 1.9.2
CRuby Redmine #5864 is fixed on 1.9.3 and use correct encoding names
m::N with module sentence returns its name

The module sentence registers its ID.
In this case, the module knows that it is called as "N" and its outer module.
3rd argument of IO.new is 1.9.3 or later
CRuby r39628 added Singleton class to ancestors [Feature #8035]
Add blank version files
Ignore deprecated warnings
use Thread.pass in looping threads to ensure others get a chance to run
.gitignore rubyspec_temp so that no one accidentally commits it.
Add configuration for building rubyspec on Travis CI on all supported rubies.
Use pragma GCC diagnostic push/pop

Note that push/pop is GCC 4.6 feature.
Use should_not raise_error to verify it don't raise error
Don't notify from travis
build only ruby branch
Try small sets for testing travis
Use nurse's mspec
Set target binary as ruby
Changed Ruby 2.0 target to 'ruby'. [ci skip]