Fixing custom range support.
Fixing custom range support.

Check for `singleDatePicker` should check for boolean value, not `undefined`.

shijistar/ember-cli-daterangepicker,gregjopa/ember-cli-daterangepicker,josemarluedke/ember-cli-daterangepicker,gregjopa/ember-cli-daterangepicker,shijistar/ember-cli-daterangepicker,cataline/ember-cli-daterangepicker,josemarluedke/ember-cli-daterangepicker,cataline/ember-cli-daterangepicker