normalize annotation thickness to preserve size

...src/main/java/org/bigbluebutton/common/messages/Util.java

...gbluebutton/modules/whiteboard/business/shapes/Ellipse.as

...n/modules/whiteboard/business/shapes/EllipseAnnotation.as

.../bigbluebutton/modules/whiteboard/business/shapes/Line.as

...tton/modules/whiteboard/business/shapes/LineAnnotation.as

...igbluebutton/modules/whiteboard/business/shapes/Pencil.as

...odules/whiteboard/business/shapes/PencilDrawAnnotation.as

...luebutton/modules/whiteboard/business/shapes/Rectangle.as

...modules/whiteboard/business/shapes/RectangleAnnotation.as

...button/modules/whiteboard/business/shapes/ShapeFactory.as

...bluebutton/modules/whiteboard/business/shapes/Triangle.as

.../modules/whiteboard/business/shapes/TriangleAnnotation.as