Array.map for strings.
npm install map-stringArray.map for strings.

``sh`
npm install map-string
`js
const mapString = require("mapString");
mapString("abcd", (val) => {
if (val === "b") return "!"
return val
});
//=> 'a!cd'
`
#### string
Type: string
The string to iterate.
#### iteratee
Type: function(value, index, string)`
The iteratee to use.