Gleefre/define start function

[Gleefre]

Reopens #78. Also see #65 and #58.

I don't really like the API to be honest, so it is still a draft.

[vydd]

Hey @Gleefre,

I don't think I understand why define-start-function is better than make-executable. I get the logic behind adding options to define-start-function though, but it feels unnecessarily custom.

In my mind, we could have a general make-executable method that works across various distributions, and we could make it call additional methods when they are defined for setup / cleanup / etc (if we don't want to have users directly define before/after). So, something like

(defmethod before-export ((sketch foo))
  ...)

defmethod after-whatever ((sketch foo))
  ...)

(make-executable 'foo :out "foo.exe") ; let's imagine we are on Windows!

[Gleefre]

Closing for now