Run shellcheck and some more manual fixes

[Artoria2e5]

• ARGV is now an array. Should fix #32.
• Quotes and stuff, also in generated code.
• Not using ... is a good idea because it effs up badly when you nest them. It's also in shellcheck.
• Catch bad args in tickVars. And don't exit on help -- you are a function, act like one.

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POSIX interaction, in case people want it later:

• No arrays, but we aren't gonna do the transpiling anyways.
• No +=, so it's gonna be dreadfully slow for long args. Remember the quadratic string append stuff in JS? Yeah it's exactly that.
• No ${var/pat/sub}, so dreadfully slow again. Prefix and suffix trimming is available though.
• No (( ... )), but [ "$(( ... ))" -ne 0 ] is the same. Except for ++.
• No <<<, so I am effing myself up.

In addition, echo is a wack, but we can always roll our own with printf.