Add --hydra-config flag to override concurrency from CLI

[patcon]

Related: #131

Thanks for considering, and thanks for all your work on maintaining this tool! :)

[patcon]

Ah, I think I may have found a bug. Seems that when JSON config was being merged from --typhoeus-config, it was string keys being merged with symbolized keys internally. Not sure how gracefully this was handled. There were no errors when this happened to typhoeus, but hydra was throwing errors about "max_concurrency" not being valid option.

(Note the double values at the end of the output debug string in screenshot)

If we instead parse JSON with JSON.parse(foo, { symbolize_names: true }), then these merge more cleanly. Going to do that, but lemme know if it should be in a separate PR)

[patcon]

Perhaps you could advise on whether this is an acceptable fix, before I start investigating/resolving these test failures. Seems to be an issue with checking a value called "myValue", which may be related to symbolization

[gjtorikian]

Ah, thanks for adding this!

I'm confused why the keys suddenly need to be symbolized, but I don't think that has any effect on the end user, so I'm fine with it. And yes, it looks like the test just needs to be turned into a symbol key rather than a string.

[patcon]

yay! thanks! will fix that 🙌

(Might be a JSON stdlib change way back, maybe was an old ruby version that worked the other way)

[patcon]

k pushed fix! Should be good to merge. Thanks @gjtorikian 🙌

[gjtorikian]

Thanks again!