Improve zetuptoolz' logging of what it is doing.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Bump zetuptoolz version number.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Rename zetuptoolz egg to reflect new version number.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Refactoring to move the not_import_versionable and ignorable package lists to _auto_deps.py.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Move require_more() to top-level.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Make dependencies different for Windows and non-Windows. fixes #2249

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Only allow pyOpenSSL >= 0.14 if it is already installed. fixes #2193

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
_auto_deps.py cosmetics and cleanup.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
.travis.yml: remove workaround to install Twisted 13.0 which should no longer be needed.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Specify the setuptools egg filename explicitly rather than globbing for it.
(Note that if the version changes in future, this will fail loudly so we'll know we have to change it.)

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Improve comments in _auto_deps.py. refs #2249, #2028, #2193, #2005, #1258

Signed-off-by: Daira Hopwood <daira@jacaranda.org>