Upgrade RubySpec
Upgrade RubySpec

Commit: a5654391c23a783cee76de3c279d7616b4683c92

* chomp must return an empty String when arg == self
* Array#difference should run shared specs for 'difference' method

Mogztter/opal,opal/opal,kachick/opal,Mogztter/opal,opal/opal,Mogztter/opal,Mogztter/opal,kachick/opal,kachick/opal,opal/opal,opal/opal,kachick/opal