herbstluftwm: 0.8.3 → 0.9.1

Also enables the packages' tests.
The tests need a few patches to fix runtime generated script's shebangs.
There is also a fix to pass PATH environment variable to subprocess'
calls so that they can find some binaries (like xterm).

pkgs/applications/window-managers/herbstluftwm/test-path-environment.patch

@@ -0,0 +1,10 @@
+--- a/tests/conftest.py
++++ b/tests/conftest.py
+@@ -43,6 +43,7 @@
+         self.next_client_id = 0
+         self.env = {
+             'DISPLAY': display,
++            'PATH': os.environ['PATH']
+         }
+         self.env = extend_env_with_whitelist(self.env)
+         self.hlwm_process = hlwm_process