readme and add 3.9

Author: michelp

README.md

@@ -1,20 +1,22 @@
 # postgresql-wheel
 
-A Python wheel for Linux containing a locally installable PostgreSQL
-database server.
+A Python wheel for Linux containing a complete, self-contained,
+locally installable PostgreSQL database server.
 
 All servers run as the Python process user in a local path, so this
-wheel does not require root or sudo privledges.
+wheel does not require root or sudo privledges.  Databases can be
+initialized in any directory.
 
 Servers can be setup and torn down in test fixtures with no additional
 outside dependencies.
 
-Currently this wheel only works for most flavors of Linux.  MacOS and
-maybe even Windows are doable... by someone else.
+Currently this wheel only works for most flavors of Linux.
 
 Postgres is compiled in the same "manylinux" environments provided by
 the [cibuildwheel](https://cibuildwheel.readthedocs.io/en/stable/)
-tool using [Github Actions]() and directly archived into the wheel's "package_data".
+tool using [Github
+Actions](https://github.com/michelp/postgresql-wheel/blob/main/.github/workflows/wheels.yml)
+and directly archived into the wheel's "package_data".
 
 The wheel can be installed with pip:
 

setup.py

@@ -22,5 +22,5 @@ def package_files(directory):
     package_data={"postgresql": package_files("postgresql")},
     setup_requires=["cffi"],
     cffi_modules=["postgresql/build.py:ffibuilder"],
-    python_requires=">=3.8,<3.9",
+    python_requires=">=3.7,<3.10",
 )