Replace Makefile with bash script

Makefile

-PANDOC := $(shell which pandoc)
-VIRTUALENV := $(shell which virtualenv)
-
-ifeq ($(PANDOC),)
-$(warning No pandoc binary found)
-endif
-
-ifeq ($(VIRTUALENV),)
-	$(warning No virtualenv binary found)
-endif
-
-all: deps test doc
-
-venv:
-	@virtualenv venv
-	@venv/bin/pip install tox nose epydoc
-
-test: venv
-	@venv/bin/tox
-
-doc: venv
-	@venv/bin/epydoc --config=epydoc.ini --no-private
-	@pandoc --from=markdown --to=rst --output=README.rst README.md

build.sh

+#!/bin/bash
+
+function error {
+    echo "Error: $1" 1>&2
+    exit 1
+}
+
+if [ -z $(which pandoc) ]; then
+    error "Missing pandoc binary"
+fi
+
+if [ -z $(which virtualenv) ]; then
+    error "Missing virtualenv binary"
+fi
+
+if [ ! -d venv ]; then
+	virtualenv venv || error "virtualenv failed"
+	venv/bin/pip install tox nose epydoc || error "pip failed"
+fi
+
+venv/bin/tox || error "tox failed"
+venv/bin/epydoc --config=epydoc.ini --no-private || error "epydoc failed"
+
+pandoc -f markdown -t rst -o README.rst README.md || error "pandoc failed"
+