API : 'alt' to invert selection instead of 'shift'
API : 'alt' to invert selection instead of 'shift'

Change modifier key for inversion (subtraction) to 'alt' to match the
standard key bindings in photoshop and company.

sameera2004/xray-vision,sameera2004/xray-vision,giltis/xray-vision,licode/xray-vision,ericdill/xray-vision,licode/xray-vision,giltis/xray-vision,ericdill/xray-vision