Debian Jessie installation instructions for pip3

[hoxu]

Dependencies:

sudo apt-get install python3-dev python3-pip libacl1-dev

Installation with a virtualenv:

sudo apt-get install python3.4-venv
pyvenv-3.4 virtualenv-attic
source virtualenv-attic/bin/activate
pip3 install attic

If I created a PR for covering this in the installation section, would you accept it?

[benozol]

I just went through the same process − and also had to install libssl-dev and libfuse-dev (the latter for attic mount).