Caesar cipher

[TheSTL]

⚠️ Issue

Caesar cipher should raise and error when second argument is not a number, instead it's returning a string of "undefinedundefinedundefined"

[ashokdey]

Thanks, @fcosueza, for pointing out this in #40. I am taking up this.

[fcosueza]

You're welcome 😃

[Omkaragrawal]

Hey,
I would like to take up the task for Caesar Cipher, including testing, etc.

[ashokdey]

Okay, go ahead @Omkaragrawal 👍