Update Gherkin and add ability to work with multiple languages

[AndreSteenveld]

• Gherkin was updated
• All the projects now target .NET Standard 2.0
• Gherkin tests in other languages are now possible

Before changing this I want to add a few more tests in emoji-lang to exercise all keywords (examples, rules, etc).

Stuff I've noticed and would like to address:

• Not all files are consistent with indenting (some are tabbed, some are spaces, some are mixed)
• Not all files have the same line endings
• The unit test project has a GherkinFeatureBuilder which isn't used consistently

[AndreSteenveld]

I'm probably missing something but where can I find the appveyor.yml file? (https://www.appveyor.com/docs/build-configuration/#configuring-build)

[ttutisani]

I'm probably missing something but where can I find the appveyor.yml file? (https://www.appveyor.com/docs/build-configuration/#configuring-build)

There is no yml file yet. Everything worked with defaults so far, so the yml file was not necessary. If you need it and know how it works, feel free to create one.

[AndreSteenveld]

I got appveyor working on my account but don't have access to your account so the builds will fail here until otherwise configured. I commited the appveyor.yml file in the root which seems to work.

[ttutisani]

Sorry, I was in the middle of things. Is this PR ready for review?

[AndreSteenveld]

Yes, there are a few settings that need tweaking in appveyor settings to make sure it picks up the the yaml file over the settings configured in the GUI. (settings, nuget keys, etc) Other than that I think it is fine. I've produced a local nuget package to keep momentum I've built up in the project I wanted to use this for and so far haven't found issues.

Other than the stuff I mentioned in opening message of this PR I think this is OK. I would like to add a two features in the future;

• Using named groups to map to a paramater
• Adding more {...} processors, or at least making it easier to register your own

Should I create a few tickets for those?

[ttutisani]

Yes, please create the issue tickets for each request separately. Meanwhile, I will review this PR.

[ttutisani]

Good work. Please address the comments and I will review them again. Thanks!

[ttutisani]

I need to check if these changes are necessary.

[ttutisani]

Same here. How is this different from what the appveyor does by default?

[ttutisani]

Why partial?

[ttutisani]

I see you have added an emoji version for every test. I think that's too much for one feature, otherwise the codebase will grow exponentially and maintenance will be a headache. Please remove all these new feature files for emoji. Just create one feature file and one feature class for emoji version and that will prove the point. You can make that feature as advanced as you can, but keep everything in one feature. I will not be reviewing so many files for the same thing.

[AndreSteenveld]

I have been busy and on vacation for the last two weeks so I haven't spent any time on this. Later this week I want to spend some time cleaning up the emoji feature files and making sure there is a relatively complete feature to test with emoji which will hopefully take away most of the noise from the project consumer.

[ttutisani]

@AndreSteenveld any news? I haven't heard back from you lately.