Make stdout deprecation warning more specific
Make stdout deprecation warning more specific

In a Rails application with a large number of dependencies, it's hard to
know which library is emitting a warning. This adds "capybara-webkit" to
the deprecation warning.

Resolves #607.

irfanah/capybara-webkit,addicted2sounds/capybara-webkit,irfanah/capybara-webkit,phlizik/capybara-webkit,mhoran/capybara-webkit,cognetoapps/capybara-webkit,avantcredit/capybara-webkit,jorihardman/capybara-webkit,nritholtz/capybara-webkit,tasboa/capybara-webkit,dstnation/capybara-webkit,jorihardman/capybara-webkit,conciergelive/capybara-webkit,betelgeuse/capybara-webkit,twalpole/capybara-webkit,msbit/capybara-webkit,shopkeep/capybara-webkit,phlizik/capybara-webkit,betelgeuse/capybara-webkit,avantcredit/capybara-webkit,thoughtbot/capybara-webkit,marcisme/capybara-webkit,jorihardman/capybara-webkit,addicted2sounds/capybara-webkit,vintikzzz/capybara-webkit,marcisme/capybara-webkit,nvntd/capybara-webkit,thoughtbot/capybara-webkit,addicted2sounds/capybara-webkit,nritholtz/capybara-webkit,phlizik/capybara-webkit,irfanah/capybara-webkit,mhoran/capybara-webkit,nritholtz/capybara-webkit,msbit/capybara-webkit,tasboa/capybara-webkit,addicted2sounds/capybara-webkit,shopkeep/capybara-webkit,twalpole/capybara-webkit,twalpole/capybara-webkit,shopkeep/capybara-webkit,addicted2sounds/capybara-webkit,thoughtbot/capybara-webkit,betelgeuse/capybara-webkit,nvntd/capybara-webkit,vintikzzz/capybara-webkit,nritholtz/capybara-webkit,nvntd/capybara-webkit,marcisme/capybara-webkit,vintikzzz/capybara-webkit,phlizik/capybara-webkit,dstnation/capybara-webkit,jorihardman/capybara-webkit,irfanah/capybara-webkit,nvntd/capybara-webkit,avantcredit/capybara-webkit,nritholtz/capybara-webkit,vintikzzz/capybara-webkit,betelgeuse/capybara-webkit,tasboa/capybara-webkit,shopkeep/capybara-webkit,shopkeep/capybara-webkit,tasboa/capybara-webkit,avantcredit/capybara-webkit,conciergelive/capybara-webkit,cognetoapps/capybara-webkit,conciergelive/capybara-webkit,cognetoapps/capybara-webkit,avantcredit/capybara-webkit,dstnation/capybara-webkit,msbit/capybara-webkit,conciergelive/capybara-webkit,msbit/capybara-webkit,nvntd/capybara-webkit,betelgeuse/capybara-webkit,msbit/capybara-webkit,twalpole/capybara-webkit,cognetoapps/capybara-webkit,dstnation/capybara-webkit,marcisme/capybara-webkit,mhoran/capybara-webkit,mhoran/capybara-webkit,dstnation/capybara-webkit,tasboa/capybara-webkit,irfanah/capybara-webkit,thoughtbot/capybara-webkit,conciergelive/capybara-webkit,phlizik/capybara-webkit,cognetoapps/capybara-webkit,marcisme/capybara-webkit,jorihardman/capybara-webkit,vintikzzz/capybara-webkit