packaging: add make target for linux wheels

Having linux wheels is going to helps system without compiler or python-dev
plus speed up the installation for everyone.

I followed the manylinux example repository
https://github.com/pypa/python-manylinux-demo
to add a make target (build-linux-wheels) using
official docker image to build python 2 linux wheels
for mercurial. It generates Python 2.6 and Python 2.7 for both
32 and 64 bits architectures.

I had to blacklist several test cases for various reasons:
* test-convert-git.t and test-subrepo-git.t because of the git version
* test-patchbomb-tls.t because of warning using tls 1.0
  It's likely because the docker image is based on centos 5.0 and
  openssl is outdated.

contrib/build-linux-wheels.sh

@@ -0,0 +1,34 b''
+#!/bin/bash
+# This file is directly inspired by
+# https://github.com/pypa/python-manylinux-demo/blob/master/travis/build-wheels.sh
+set -e -x
+
+PYTHON_TARGETS=$(ls -d /opt/python/cp2*/bin)
+
+# Create an user for the tests
+useradd hgbuilder
+
+# Bypass uid/gid problems
+cp -R /src /io && chown -R hgbuilder:hgbuilder /io
+
+# Compile wheels for Python 2.X
+for PYBIN in $PYTHON_TARGETS; do
+    "${PYBIN}/pip" wheel /io/ -w wheelhouse/
+done
+
+# Bundle external shared libraries into the wheels with
+# auditwheel (https://github.com/pypa/auditwheel) repair.
+# It also fix the ABI tag on the wheel making it pip installable.
+for whl in wheelhouse/*.whl; do
+    auditwheel repair "$whl" -w /src/wheelhouse/
+done
+
+# Install packages and run the tests for all Python versions
+cd /io/tests/
+
+for PYBIN in $PYTHON_TARGETS; do
+    # Install mercurial wheel as root
+    "${PYBIN}/pip" install mercurial --no-index -f /src/wheelhouse
+    # But run tests as hgbuilder user (non-root)
+    su hgbuilder -c "\"${PYBIN}/python\" /io/tests/run-tests.py --with-hg=\"${PYBIN}/hg\" --blacklist=/io/contrib/linux-wheel-centos5-blacklist"
+done

contrib/linux-wheel-centos5-blacklist

@@ -0,0 +1,3 b''
+test-convert-git.t
+test-subrepo-git.t
+test-patchbomb-tls.t

.hgignore

@@ -62,6 +62,9 b' mercurial/mpatch.py'
 mercurial/osutil.py
 mercurial/parsers.py
 
+# Generated wheels
+wheelhouse/
+
 syntax: regexp
 ^\.pc/
 ^\.(pydev)?project

Makefile

@@ -270,6 +270,14 b' docker-centos7:'
 	mkdir -p packages/centos7
 	contrib/dockerrpm centos7
 
+linux-wheels: linux-wheels-x86_64 linux-wheels-i686
+
+linux-wheels-x86_64:
+	docker run -e "HGTEST_JOBS=$(shell nproc)" --rm -ti -v `pwd`:/src quay.io/pypa/manylinux1_x86_64 /src/contrib/build-linux-wheels.sh
+
+linux-wheels-i686:
+	docker run -e "HGTEST_JOBS=$(shell nproc)" --rm -ti -v `pwd`:/src quay.io/pypa/manylinux1_i686 linux32 /src/contrib/build-linux-wheels.sh
+
 .PHONY: help all local build doc cleanbutpackages clean install install-bin \
 	install-doc install-home install-home-bin install-home-doc \
 	dist dist-notests check tests check-code update-pot \
@@ -278,4 +286,5 b' docker-centos7:'
 	docker-ubuntu-xenial docker-ubuntu-xenial-ppa \
 	docker-ubuntu-yakkety docker-ubuntu-yakkety-ppa \
 	fedora20 docker-fedora20 fedora21 docker-fedora21 \
-	centos5 docker-centos5 centos6 docker-centos6 centos7 docker-centos7
+	centos5 docker-centos5 centos6 docker-centos6 centos7 docker-centos7 \
+	linux-wheels