tmf: Split the statistics in two separate providers

tmf: Split the statistics in two separate providers

Use separate state providers and backends (and so, two separate .ht files)
to store the statistics information. This will make it easier to eventually
swtich the event-types provider to a partial history backend - two one-liners
basically (or do we say one two-liner?)

Change-Id: If11956af12795a406f42c05b2cd67f82867850da
Signed-off-by: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
Reviewed-on: https://git.eclipse.org/r/11458
Tested-by: Hudson CI
Reviewed-by: Marc-Andre Laperle <marc-andre.laperle@ericsson.com>