Write a function that accepts a string as an argument and returns true if the string is a palindrome (the string is the same forward and backward), or false if it is not.

A string is still considered a palindrome despite letter capitalization, spaces, or punctuation.

E.g.:

isPalindrome("Star Rats!");  // true
isPalindrome("palindrome");  // false
isPalindrome("I madam, I made radio! So I dared! Am I mad?? Am I?!");  // true