1901 - Fix Welcome Page

Solution was very simple to implement, no content disposition header was
necessary.
Tested with both Firefox and Chrome, using binary image file stored in
folder, as well as with text data using LIT cap.
Merge pull request #112 from Lcstyle/master

Fix 1901 - the "Download!" button on the Welcome page leads to the file displayed in-browser instead of downloaded/saved.
travis: remove the os.statvfs debug command

According to https://github.com/travis-ci/travis-ci/issues/2788 (which
was WONTFIXED), roughly half the travis-ci buildserver fleet runs off
tmpfs volumes, which have different notions of space-free and space-used
than real filesystems. We've adapted our tests to avoid relying upon
space-used>0, and no longer need this call to investigate the problem.

refs ticket:2290
remove all the unused scripts from build_helpers

Fixes #2305.
Merge pull request #114 from zooko/2305-remove-obsolete-tools-from-misc

remove all the unused scripts from build_helpers
Delete obsolete Trove classifiers.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
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>
Make dependencies different for Windows and non-Windows.
Also move require_more() to top-level. fixes #2249

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
Accept pyOpenSSL >= 0.14 as a dependency iff it is already installed.

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>