Returns the value associated with key under group_name as a boolean.
If key cannot be found then false is returned and
throws is set to KEY_NOT_FOUND. Likewise, if the value
associated with key cannot be interpreted as a boolean then false is returned
and throws is set to INVALID_VALUE.
| this |
a KeyFile |
| group_name |
a group name |
| key |
a key |
|
the value associated with the key as a boolean, or false if the key was not found or could not be parsed. |