Add installation script for Ubuntu and its derivatives

TODO: extend README for instructions. Please do not merge yet.

install.sh

@@ -0,0 +1,56 @@
+# This file is part of the Inkscape extension 'inkscape-embroidery', 
+# an extension for machine embroidery design using Inkscape.
+
+# Copyright (C) 2017 Maren Hachmann
+
+# inkscape-embroidery is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# inkscape-embroidery is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with inkscape-embroidery.  If not, see <http://www.gnu.org/licenses/>.
+
+#!/bin/bash
+
+# we want to be in the tmp directory
+cd /tmp
+
+# delete old snap Inkscape (we really don't want a snap!)
+sudo snap remove inkscape
+
+# add stable-daily repository
+sudo add-apt-repository ppa:inkscape.dev/stable
+
+# refresh package list
+sudo apt-get update
+
+# install everything we need
+sudo apt-get install inkscape pip unzip
+
+# download lexelby's embroidery extension
+wget https://github.com/lexelby/inkscape-embroidery/archive/master.zip
+
+# unzip files
+unzip master.zip -d /tmp
+
+# change into new directory
+cd inkscape-embroidery-master
+
+# install requirements (only with user privileges, not system-wide)
+pip install --user -r requirements.txt
+
+# create extensions directory if doesn't exist yet
+mkdir -p $HOME/.config/inkscape/extensions
+
+# copy all *.py and *.inx files there
+cp *.py *.inx $HOME/.config/inkscape/extensions
+
+echo "Lexelby's embroidery extension and its dependencies have been installed,
+and your Inkscape version is now up to date.
+Any previously installed Inkscape snap packages have been removed."