added caeser cipher readme

caeser_cipher/README.md

@@ -0,0 +1,27 @@
+# Simple Caeser Cipher [En,De]coder
+
+A simple implementation of a CLI tool to work with caeser ciphers.  The default implementation is ROT-13, but can be 
+adjusted for any offset.  Works on files and string arguments passed via CLI.  
+
+```bash
+python3 caeser.py
+
+usage: caeser.py [-h] [-d] [-o OFFSET] (-f FILE | -s STRING)
+caeser.py: error: one of the arguments -f/--file -s/--string is required
+``` 
+
+```bash
+python3 caeser.py -s "have you tried turning it off and on again?"
+unir lbh gevrq gheavat vg bss naq ba ntnva?
+```
+
+```bash
+python3 caeser.py -d -s "unir lbh gevrq gheavat vg bss naq ba ntnva?" 
+have you tried turning it off and on again?
+```
+
+```bash
+python3 caeser.py -s "have you tried turning it off and on again?" -o -4
+dwra ukq pneaz pqnjejc ep kbb wjz kj wcwej?
+```
+