common.core: move saturated math to common core

common.core: move saturated math to common core

As overflow problems are more and more common, it is justified
to make saturated (clamped) math available to all packages.

Test coverage is 100%, the code has to be rigourously tested as
this is part of the base of trace compass now.

Change-Id: Icf9771162230b8ff0371015ed0f39cc5ff07a06f
Signed-off-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Reviewed-on: https://git.eclipse.org/r/78107
Reviewed-by: Hudson CI
Reviewed-by: Patrick Tasse <patrick.tasse@gmail.com>
Tested-by: Patrick Tasse <patrick.tasse@gmail.com>