tmf: Replace event matching API to use Collection

tmf: Replace event matching API to use Collection

instead of straight arrays. This is more flexible, and indicates
that there is no notion of ordering of the traces. Had to replace
one instance of List.get(i) with a map of traces.

Change-Id: Ia25d79b4735b0acb5d4c56975e5e384ad39ad583
Signed-off-by: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
Reviewed-on: https://git.eclipse.org/r/24078
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>