docs: clean up readthedocs URLs

It will redirect to the canonical URL https://*.readthedocs.io/en/latest , and
there is no point in linking to /en/latest .

py3: switch to use Python 3 interpreter, temporarily leaving many things very broken until they have been migrated/fixed in a reviewable way

Bump Mercurial minimum version to 5.2 - the first version that claim stable py3
support.

scripts/make-release: update URL of read-the-docs Builds page

Old one no longer works.

scripts/make-release: fix check of dist file content after commit 7c7d6b5c07c7

The kallithea repo recently gained a .mo file for English, but all .mo files
are filtered out when comparing the list of files in the tarball.

Fix by filtering out the new .mo file when getting the repo manifest.

scripts/make-release: install ldap and pam to fix isort instabilities

isort (triggered by scripts/whitespacecleanup.sh) needs to know which
modules are local and which are not, to separate them with a newline. If a
module cannot be found, it will be treated as local, apparently.

When ldap is not installed in the current environment, a difference was
created by isort in kallithea/bin/ldap_sync.py.

docs: always use dev_requirements.txt together with main version constraints in setup.py

pip isn't good at considering old constraints when installing or updating
packages later. Instead, install everything at once.

Note: pip and setuptools are usually installed automatically and could perhaps
be removed from documentation. But for now, let's keep it.

scripts/make-release: print out shortlog for inclusion in release announcements

The revset should generate the correct list compared with the last tagged
release on the stable branch.

The same revset should be used as a basis for release notes.

scripts/make-release: fix PyPI upload by using twine

Upload via 'python2 setup.py sdist upload' is deprecated.

Worse, for unknown reasons it stopped working for 0.4, even though 0.3 did
pretty much the same.

Following output was given:

WARNING: Uploading via this command is deprecated, use twine to upload
instead (https://pypi.org/p/twine/)
Traceback (most recent call last):
File "setup.py", line 160, in <module>
""",
File "/tmp/kallithea-release-JtnfD/lib/python2.7/site-packages/setuptools/__init__.py",
line 145, in setup
return distutils.core.setup(**attrs)
File "/usr/lib64/python2.7/distutils/core.py", line 151, in setup
dist.run_commands()
File "/usr/lib64/python2.7/distutils/dist.py", line 953, in run_commands
self.run_command(cmd)
File "/usr/lib64/python2.7/distutils/dist.py", line 972, in run_command
cmd_obj.run()
File "/tmp/kallithea-release-JtnfD/lib/python2.7/site-packages/setuptools/command/upload.py",
line 26, in run
orig.upload.run(self)
File "/usr/lib64/python2.7/distutils/command/upload.py", line 62, in run
self.upload_file(command, pyversion, filename)
File "/tmp/kallithea-release-JtnfD/lib/python2.7/site-packages/setuptools/command/upload.py",
line 136, in upload_file
value = str(value).encode('utf-8')
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc5 in position
825: ordinal not in range(128)

The error is pointing to a unicode character in the README.rst file.

The proposed 'twine' command does not have this problem. As it seems that
this is the future, we won't waste more time investigating the problem with
'sdist upload', and start using twine from now on.

scripts/make-release: remove uploading of PyPI docs

This is now replaced by ReadTheDocs.

make-release: only specify Sphinx once for pip install

It failed with:

Double requirement given: Sphinx<1.8 (from -r dev_requirements.txt (line 8)) (already in Sphinx, name='Sphinx')

remove references to pythonhosted.org (issue #293)

The pythonhosted service is no longer supported.
Update links to point to docs.kallithea-scm.org (which redirects to
kallithea.readthedocs.io)

While at it, fix the whoosh pythonhosted.org reference as well.

remove references to pythonhosted.org (issue #293)

The pythonhosted service is no longer supported.
Update links to point to docs.kallithea-scm.org (which redirects to
kallithea.readthedocs.io)

While at it, fix the whoosh pythonhosted.org reference as well.

make-release: use a fresh virtualenv for building the release

A user-provided virtualenv could contain extra packages or different
versions, which may mask problems inside Kallithea.

make-release: remove instruction about updating copyright/contributors

The copyright script is now run by the script itself, so a warning to run it
is no longer necessary.

make-release: import version and copyright updates from default branch (dba4e770d4b6)

make-release has been improved on the default branch in commit dba4e770d4b6,
and that version of the script also almost works on stable.

There are some parts we don't have in stable branch: dev_requirements.txt,
run-all-cleanup, and a working dist file content check:

The MANIFEST.in file on the stable branch is not complete.
Most of the missing entries could simply be added
(.travis.yml, requirements.txt, tox.ini, and scripts/*) but there is one
problematic entry: kallithea/i18n/en/LC_MESSAGES/kallithea.mo.
In the check command, all .mo entries are filtered out, causing a remaining
diff for the English .mo.

As that file has been removed on the default branch already, and the missing
entries are not important for the release anyway, simply drop the check
for now.

make-release: cleanup and fix bitrot

Try to make the build process more stable and maintainable.

So far, this leaves a problem with node_modules/bootstrap/ and
kallithea/public/css/style.css missing from the release .tar.gz .