Returns a string with the first letter of each word capitalized.
function capitalize(str: string, lowercaseOthers?: boolean): string
// Example:
capitalize("stephen") //=> "Stephen"
capitalize("hello world") //=> "Hello World"
capitalize("hELLO", true) //=> "Hello"
capitalize("hELLO", false) //=> "HELLO"
NOTE: Optionally pass in boolean to convert following characters to lower case