No source-disribution for python pip for 0.8.4 and 0.8.5

[ErikDeSmedt]

I am trying to install wallycore on an alpine-linux docker-image.

Alpine linux is using musl instead of glibc. Since 0.8.4 wallycore is released a built-distribution for the manylinux-platform. Unfortunately, manylinux does not support musl and wallycore cannot be installed.

I propose to include a source-distribution in every python-release of wally-core.