Default to running Klaus in Python3

Install python3 plugin for uwsgi

Check that README is actually a blob, not a tree

repo.py: fix cloneurls showing up as b'http://example.org/foo\n'

Simply converts all known readme naming conventions and file names
within the tree to lower case on file discovery. This ensures double the
coverage of acceptable readme filenames.

This patch is the result of a discussion over making the known readme
naming conventions extendable by the user on the Klaus mailing list.
[ See https://groups.google.com/forum/#!topic/klaus-users/mXjDxyqbeMQ ]

added power support arch on yml file.

Added power support for the travis.yml file with ppc64le. This is part of the Ubuntu distribution for ppc64le.

fix 'pip3' missing

Currently only available through manual make_app() call

Not working on caching at the moment...

This reverts commit e21cf6a3.

Use an older version of Dulwich on Python 2

Dulwich 0.20.0 dropped support for Python 2 and 3.4.

* Fix import of ProxyFix for werkzeug 1.0.x

Fix import of ProxyFix for werkzeug 1.0.x

* Require Werkzeug>=0.15.0 for werkzeug.middleware.proxy_fix

Require Werkzeug>=0.15.0 for werkzeug.middleware.proxy_fix

* Add Dockerfile

* add KLAUS_VERSION build arg