docs: use markdown for readme file

README.md

@@ -0,0 +1,11 @@
+
+# rattail-cognitive
+
+Rattail is a retail software framework, released under the GNU General Public
+License.
+
+This package contains hardware interfaces for
+[Cognitive](http://www.cognitive.com/) devices.
+
+Please see Rattail's [home page](https://rattailproject.org/) for more
+information.

README.txt

@@ -1,13 +0,0 @@
-
-rattail-cognitive
-=================
-
-Rattail is a retail software framework, released under the GNU General Public
-License.
-
-This package contains hardware interfaces for `Cognitive`_ devices.
-
-Please see Rattail's `home page`_ for more information.
-
-.. _Cognitive: http://www.cognitive.com/
-.. _home page: https://rattailproject.org/

pyproject.toml

@@ -8,7 +8,7 @@ build-backend = "hatchling.build"
 name = "rattail_cognitive"
 version = "0.4.0"
 description = "Hardware Interfaces for Cognitive Devices"
-readme = "README.txt"
+readme = "README.md"
 authors = [{name = "Lance Edgar", email = "lance@edbob.org"}]
 license = {text = "GNU GPL v3+"}
 classifiers = [