7bf209db50
Currently "/usr/bin/env python" is rewritten to "/nix/store/.../env python". That doesn't really improve anything because the interpreter still have to be located in $PATH at runtime. The result is that many nix package expressions do .../bin/env fixup themselves. Instead of everyone having to do this patching locally, add the functionality to the standard environment patchShebangs function so that everyone can benefit.