Add catmux script

This helper should maket it easier to interact with running catmux sessions.

script/catmux

@@ -0,0 +1,9 @@
+#!/bin/bash
+# This script serves as an entry point to use the `catmux` command similar to
+# the `tmux` command. Since catmux starts its sessions on its own server by
+# default this script should provide a simple alternative to interact with
+# catmux sessions easily.
+
+TMUX_SERVER="${CATMUX_DEFAULT_SERVER:-catmux}"
+
+tmux -L $TMUX_SERVER $@

setup.py

@@ -19,6 +19,7 @@
     entry_points={
         "console_scripts": ["catmux_create_session=catmux.catmux_create_session:main"]
     },
+    scripts=["script/catmux"],
     classifiers=[
         "Programming Language :: Python :: 3",
         "License :: OSI Approved :: MIT License",