Moved this too soon, verify_python() expects bin/python to be created first

plugins/python-build/bin/python-build

@@ -922,6 +922,9 @@ build_package_pyston() {
   mkdir -p "${PREFIX_PATH}/"
   cp -fR . "${PREFIX_PATH}/"
   chmod +x "${PREFIX_PATH}/"pyston
+  # FIXME ugly hack below adapted from
+  # https://github.com/dropbox/pyston/blob/master/docker/pyston/Dockerfile
+  ( cd "${PREFIX_PATH}/" && ./pyston virtualenv/virtualenv.py . )
 }
 
 build_package_ironpython() {