Release v1.0.491

Release version v1.0.491

Metacello new
    baseline: 'GToolkitForPharo9';
    repository: 'github://feenkcom/gtoolkit:v1.0.491/src';
    load

All commits (including upstream repositories) since last build:
https://github.com/feenkcom/gtoolkit/commit/a37ef4 by onierstrasz
typo