Support "build mode" (prod, debug) when compiling the PHAR

[dkarlovi]

Feature Request

See #331 (comment)

Idea is something like

box compile --debug

vs

box compile

[theofidry]

the --debug flag already exists though, it is the shipped PHAR code extracted into a tmp directory.

That said I don't think it's incompatible with #331. Chances are, even if the final result is a binary, I would at the very least keep the PHAR version around. --debug would also still work as it currently does.

One thing I am a lot less sure about (from a code PoV, not feature-wise) is shipping the req. checker for the PHAR alone and not when in the lib. To be seen

[dkarlovi]

The flag can be anything, this was just an example, you might opt to invert the default and use --release to say you want the final, best, most optimized version of PHAR and/or binary.