Started looking at using topology data to generate more datapoints to help
group events on. Hopefully should be able to group events between sites
that share common paths (at this stage I'm planning on starting with the
AS path) as well as those that share sources and targets. As part of this
added an event detector to alert on major path changes between sites and
realised that there appears to be a bug in the AMP code to determine
common paths. Spent some time trying to track it down and it looks to be
due to counting the sample time period incorrectly, which I'm now trying
to fix.

Figured out the cause of the AMP data interface module crashing on newer
php/apache. An incorrectly sized variable was being used in the c portion
to receive data from the php portion and along the way it was clobbering
something it shouldn't have. I'm sure the compiler warned about this last
time, but not in this case.