GitLab

* New entry points are packaging/build_wheel.sh and packaging/build_conda.sh. The only mandatory environment variable you have to set is PYTHON_VERSION
* CircleCI configuration uses 2.1-style parametrized builds to let you toggle python version, etc. as you do builds. We create a separate job per build configuration for maximum parallelism
* build_tools/packaging got moved to packaging, to be in-line with directory structure in torchvision
* The build_conda.sh and build_wheel.sh delegate most of the heavy lifting to pkg_helpers.bash, which defines a number of bash functions for performing common operations. The intent is that I'll copy-paste this file between other domain API projects.
* TORCHAUDIO_ prefix removed from envvars, so that I can more easily share packaging scripts between projects
* BUILD_VERSION is completely gone; just change the version number if you need to rebuild
* No more logic for cloning and checking out a fresh copy of torchaudio

Billing of changes:

* Can now toggle what branch is built using BRANCH envvar
* PyTorch nightly we were built against is hardcoded into conda meta.yaml
* Disable Conda Python 3.5 builds as we don't have nightlies for torch at the moment
* No more torchaudio-cpu or torchaudio-nightly suffix
* Remove librosa from testing stanza, so that conda build works with stock anaconda channel
* Change convention on PREFIX to be what we previously called $PREFIX/audio
* Make build_from_source.sh cd-neutral

Signed-off-by: Edward Z. Yang ezyang@fb.com

* Packaging improvements for nightlies

- Instructions for how to install stable and master binaries,
  without hardcoding wheel filenames
- Turn on Python 2 build (numba is only needed for testing)
- Make builds a little more hermetic
- Prefer building against nightly CPU-only torch build
- Don't install all of requirements.txt, it's not necessary
- Updates for OS X too, including portability issues
Signed-off-by: Edward Z. Yang <ezyang@fb.com>

Signed-off-by: Edward Z. Yang <ezyang@fb.com>

Signed-off-by: Edward Z. Yang <ezyang@fb.com>