tmf: add abstract bar chart viewer on top using swt chart

It also adds a special histogram tooltip provider as well as an
example implementation (New Histogram view) that uses the swt chart
framework.

Change-Id: I03890eaf7a79ef7d9a48c23b26c49dca9544ea50
Signed-off-by: Bernd Hufmann <Bernd.Hufmann@ericsson.com>
Reviewed-on: https://git.eclipse.org/r/20085
Tested-by: Hudson CI
Reviewed-by: Genevieve Bastien <gbastien+lttng@versatic.net>
IP-Clean: Genevieve Bastien <gbastien+lttng@versatic.net>
Tested-by: Genevieve Bastien <gbastien+lttng@versatic.net>
Reviewed-by: Bernd Hufmann <bernd.hufmann@ericsson.com>
Tested-by: Bernd Hufmann <bernd.hufmann@ericsson.com>