promptBool prompt [default]
promptBool prompts the user with prompt and returns the user's response
interpreted as a boolean. If default is passed and the user's response is
empty then it returns default. The user's response is interpreted as follows
(case insensitive):
| Response | Result |
|---|---|
| 1, on, t, true, y, yes | true |
| 0, off, f, false, n, no | false |