Lots of improvements everywhere

test_qemu.xsh

@@ -0,0 +1,16 @@
+#!/usr/bin/env xonsh
+source test.xsh
+
+def main():
+    # Equivalent of `set -e` in Bash
+    $RAISE_SUBPROC_ERROR = True
+    for distro in get_builds():
+        print(f"Trying {distro}")
+        ./test.xsh -b @(distro) -p qemu.x86_64 --headless
+        rm -r serial-output-qemu* output_qemu* *.box
+        for x in range(10):
+            print("***" * 20)
+
+
+if __name__ == '__main__':
+    main()