Add Turbolinks 5 Support Version Check

[aaronvb]

• Add version check by using feature detection.
• Update dummy app to use Turbolinks 5

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Alternate method to #264

[justin808]

@aaronvb this looks great

Couple things:

1. Update the

https://github.com/shakacode/react_on_rails/blob/master/docs%2Fadditional_reading%2Fturbolinks.md

with some info on this.

1. Can we have travis run both? I'm pretty sure we can with 2 env setups (@dylangrafmyre)

I'd like to get this into v3. I'll merge tomorrow once I hear back.

[aaronvb]

@justin808 I couldn't get rspec to recognize two different versions of turbolinks because it seems to always default back to the turbolinks in the root Gemfile.

I tried using an ENV variable wrapped around the gem include and having a new rake task invoke it, but that didn't work.

if ENV["DISABLE_TURBOLINKS"].nil? || ENV["DISABLE_TURBOLINKS"].strip.empty?
  if ENV["TURBOLINKS_5"].nil? || ENV["TURBOLINKS_5"].strip.empty?
    gem 'turbolinks', '2.5.3'
  else
   gem 'turbolinks', '~> 5.0.0.beta' 
  end
end

I also tried setting up a 2nd dummy app with turbolinks 5 in the gemfile and it would still install the turbolinks from the root Gemfile. I know @robwise wrote something about the gems in the root Gemfile being used for the dummy app and travis-ci, maybe he can shed some light here.

[aaronvb]

Update: I may have found a way test both versions of Turbolinks. Running on CI right now.

[aaronvb]

Any gems that are used in spec/dummy need to be installed before running the tests because Travis-CI will look for the source here when running bundle install in the spec/dummy folder. This basically tells travis-ci to install turbolinks classic and turbolinks 5.

[aaronvb]

Working on doc update.

[justin808]

👏 👏 👏 👏 👏 👏 👏

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Reviewed 7 of 8 files at r1, 3 of 3 files at r2.
Review status: all files reviewed at latest revision, 2 unresolved discussions.

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