CTabFolderRenderer with flag that take into account carriage return for multi line.
Addition of Snippet371.
Addition of Javadoc on CTabItem.setText.
Addition of same cross platform behavior relating to the drop-down menu for additional tabs.

Change-Id: Ib45891dcc90727830262887745c8ec1ad9be451d
Signed-off-by: ncazottes <nicolas@cazottes.net>