Adds a 2to3 python conversion bash script

* includes flag to ignore unicode (fixes #79)
* helps keeps py3 version up to date with py2 version

source/build-latest-py3-version.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+# project: Nerd Fonts (https://github.com/ryanoasis/nerd-fonts)
+# version: 0.8.0
+# Executes the 2to3 conversion to generate latest py3 version of font patcher
+
+# Check for 2to3
+type 2to3 >/dev/null 2>&1 || {
+  echo >&2 "2to3 must be installed before running this script."
+  echo >&2 "Please see details at"
+  echo >&2 "https://docs.python.org/2/library/2to3.html"
+  exit 1
+}
+
+# -x unicode: ignore changing unicode to str
+# purpose: to prevent 2to3 by default from changing 'unicode' to 'str'
+# because in FontForge 'str' is not an attribute of the glyph object
+# for more information:
+# see: https://docs.python.org/2/library/2to3.html#to3-fixers
+# see: https://github.com/ryanoasis/nerd-fonts/issues/49
+# see: https://github.com/ryanoasis/nerd-fonts/issues/79
+2to3 -x unicode -n -w ../font-patcher --add-suffix=-py3
+
+# fix environment (first line in file)
+# from `/usr/bin/env python2` when it should
+# be `/usr/bin/env python3`
+# using 1 as line number and '%' as delimiter:
+sed -i '1s%.*%#!/usr/bin/env python3%' ../font-patcher-py3