README.md: Add tmux.conf to the "most important files" list
-rw-r--r-- 110 .gitignore
-rw-r--r-- 1284 README.md
drwxr-xr-x - debian
drwxr-xr-x - doc
drwxr-xr-x - etc
drwxr-xr-x - usr_share_grml