Install on Ubuntu 16.04.3 - python 3 set as the default python breaks install script

[mdamien]

To be specific, it's in build/quick_ref.py, #!/usr/bin/env python should be #!/usr/bin/env python2

This change may be needed on other files, as you wish.

Also, on a related note, when running build/dev.sh minimal, libc.so is linked to _devbuild/py-ext/x86_64/libc.so but the generated file is _devbuild/py-ext/x86_64/libc.cpython-35m-x86_64-linux-gnu.so. Thus raise an Import Error in native/libc_test.py when doing import libc.

And....on a still related note, when I get the correct libc.so import, I'm getting:

native/libc.c:287:3: warning: implicit declaration of function ‘Py_InitModule’ [-Wimplicit-function-declaration]
   Py_InitModule("libc", methods);
   ^

I'm investigating, maybe it would be useful to setup a Travis to show the working chain.

[andychu]

Yeah there's basically only one other person besides me working on it right now, so unfortunately the environment is pretty specific -- it's a vanilla Ubuntu 16.04 image. I'm not sure why you would want python -> python3, as that will break a lot of stuff besides OSH.

It might be a good idea to set up something like Travis, but if that were the case it would have python -> python2 since that's the default on Debian/Ubuntu and Alpine.

Issue #42 is related. I do want to specify the test environment better, which is related to the build environment, but so far it hasn't been a priority.

Some other people have changed all the shebang lines and then not contributed anything else, so honestly I'm not too excited about that as a first change :-/

[mdamien]

I agree.

I'm not sure why you would want python -> python3, as that will break a lot of stuff besides OSH.

/usr/bin/python is set as an alias for python3 for archlinux since 2010 and the latest Ubuntu LTS too, so I guess it kinds of makes sense for a lot of people.

And yes, not gonna do that as a PR 👍

EDIT: I was mistaken, python3 is not yet the default in Ubuntu