Function encipher

pub fn encipher(text: &str) -> String

The GADERYPOLUKI is a simple substitution cipher used in scouting to encipher messages. The encryption is based on short, easy to remember key. The key is written as paired letters, which are in the cipher simple replacement. The most frequently used key is “GA-DE-RY-PO-LU-KI”. Your task is to help scouts to encrypt and decrypt thier messages. Write the Encipher and Decipher functions.

Example

encipher("ABCD")
returns “GBCE”