Revert "removed position rounding in library"

This reverts commit 88e3db574a8bbcfede6eb059179238f8f4900b70.

Conflicts:
	gwt-connectors/src/main/java/pl/tecna/gwt/connectors/client/ConnectionPoint.java
	gwt-connectors/src/main/java/pl/tecna/gwt/connectors/client/Diagram.java
	gwt-connectors/src/main/java/pl/tecna/gwt/connectors/client/drag/EndPointDragController.java
	gwt-connectors/src/main/java/pl/tecna/gwt/connectors/client/elements/EndPoint.java
	gwt-connectors/src/main/java/pl/tecna/gwt/connectors/client/elements/Shape.java