move common code into server, update tests and makefile (#2425)

* move common code into server, update tests and makefile

remove backend directory, refactor

update smoke tests

server/__main__.py

@@ -0,0 +1,15 @@
+# Work around bug https://github.com/pallets/werkzeug/issues/461
+if __package__ is None:
+    import sys
+    from pathlib import Path
+
+    PKG_PATH = Path(__file__).parent
+    sys.path.insert(0, str(PKG_PATH.parent))
+    import server  # noqa F401
+
+    __package__ = PKG_PATH.name
+
+# Main thing
+from .cli.cli import cli  # noqa F402
+
+cli()