Merge branch 'fix/putImageData' into develop

putImageData fix done, incorporated in develop
First part of off screen canvas fixed: drawImage recognizes canvas
Fixed first part of the problem: differenciation between image and offscreen canvas.
Merge with latest develop.
Added EJCanvasBlendColor functions.
Merge branch 'develop' into fix/globalAlpha
Merge branch 'develop' into fix/offScreenCanvas
Fix crash when using multiple canvas on Android 2.3: buffers are no longer generated manually at onscreen canvas creation.
Merge branch 'develop' into fix/globalAlpha