Changes

T1593 - Adding IE8 Compatibility to processing.js version 1.2.3 - https://processing-js.lighthouseapp.com/projects/41284/tickets/1593-ie8-excanvas-compatibility-issues#ticket-1593-17

Fix: https://github.com/gkrilov/processing-js/tree/ie8

T1640 - Create ShearX and ShearY functions as well as ref tests and unit tests for Processing.js - https://processing-js.lighthouseapp.com/projects/41284/tickets/1640-shear-xyz-not-implemented