lttng2: Fix version handling for older eclipse platforms

lttng2: Fix version handling for older eclipse platforms

Older implementation of org.osgi.framework.Version have different
API for the compareTo method which causes a NoSuchMethodException.
This commit is to fix the version handling so that it is possible
to run it on older Eclipse versions (e.g. 3.6).

Change-Id: I968aec9f4fda5ff8cf2f05b23e1b544d3f8e28c8
Signed-off-by: Bernd Hufmann <Bernd.Hufmann@ericsson.com>
Reviewed-on: https://git.eclipse.org/r/12420
Tested-by: Hudson CI
Reviewed-by: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
IP-Clean: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
Tested-by: Bernd Hufmann <bernd.hufmann@ericsson.com>