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/cli/cli.py

@@ -0,0 +1,34 @@
+import click
+
+from .launch import launch
+from .prepare import prepare
+from .upgrade import log_upgrade_check
+from .. import __version__
+
+
+@click.group(
+    name="cellxgene",
+    subcommand_metavar="COMMAND <args>",
+    options_metavar="<options>",
+    context_settings=dict(max_content_width=85, help_option_names=["-h", "--help"]),
+)
+@click.help_option("--help", "-h", help="Show this message and exit.")
+@click.version_option(
+    version=__version__,
+    prog_name="cellxgene",
+    message="[%(prog)s] Version %(version)s",
+    help="Show the software version and exit.",
+)
+@click.option(
+    "--upgrade-check/--no-upgrade-check",
+    default=True,
+    show_default=True,
+    help="Check for release upgrades on start.",
+)
+def cli(upgrade_check):
+    if upgrade_check:
+        log_upgrade_check()
+
+
+cli.add_command(launch)
+cli.add_command(prepare)