:env support

[zrzka]

What's done:

• ->cli-arg-value as multimethod
• validate-fn-spec! removed (VPC related), because it fails anyway if it's wrong
• had to remove camel-snake-kebab (function remote config, json parsing), because you can provide case sensitive env variables (see screenshot below) -> it cripples variable names -> disallows local remote config comparison

What's left:

I left :cljs-lambda :env intact in this PR. This PR just adds support for :env in :cljs-lambda :defaults and in :cljs-lambda :functions. And now ...

• 0.6.5 can be released with :cljs-lambda :env and new :env, we're not going to break compatibility, they can coexist together for a while,
• 0.7 or 1.0 or ... can be the release where :cljs-lambda :env will be trashed
• or ...

Just let me know what do you think and what to do.

Part of #56.

[moea]

@zrzka That sounds like a plan - I'm going to do testing post-merge, by switching some of my functions over to use this - I'm not super worried about a potentially broken snapshot.

[zrzka]

@moea just let me know when you'll publish snapshot and I'll test it too

[moea]

@zrzka Thank you! 0.6.5-SNAPSHOT now contains these changes, I'll update it again once I merge #67

[zrzka]

@moea using 0.6.5-SNAPSHOT in one of our project along with new :env support and it looks good so far.