updated README

Author: Vincibean

README.md

@@ -1 +1,32 @@
 # cipher-cli
+Encrypt and decrypt messages using various algorithms
+
+## How to use it
+```sh
+cipher-cli v0.0.0.1, (C) Vincibean
+
+algo [COMMAND] ... [OPTIONS]
+  Encrypt and decrypt messages using various algorithms
+
+Common flags:
+  -e --encrypt          Encrypt a message
+  -d --decrypt          Decrypt a message
+  -m --msg=ITEM         The message to encrypt / decrypt
+  -? --help             Display help message
+  -V --version          Print version information
+     --numeric-version  Print just the version number
+  -v --verbose          Loud verbosity
+  -q --quiet            Quiet verbosity
+
+algo caesar [OPTIONS]
+  Use Caesar's encryption / decryption algorithm
+
+  -n --numkey=INT       The integer to use as key. It can be either a
+                        positive or a negative number
+
+algo vigenere [OPTIONS]
+  Use Vigenere's encryption / decryption algorithm
+
+  -s --stringkey=ITEM   The string to use as key. It must not be an empty
+                        string
+```