SKIPT_LIST is now a regex finder instead of having to especify the exact metric name

Hello there!

This adds a regex to the in_skip_list check so it will work with partial names for metric names.

This is a lifesaver in cases where you are generating the metrics automatically from an undetermined number of machines which can grow at any given moment.

I'll just explain our case, we have some ganglia metrics in our platform so I made a script that extracts them and sends them to horizon. The metric name is automatically generated from the platform_name.machine_name.metric_origin.metric_name and this machines can come up at any moment or go down at any moment so its not feasible to set the skip_list to anything as the platform name can change, and the machine name as well.

So in order to ignore metrics like whatever.whatever.hdd.BytesRead this regex will match either the origin (so we will use '.hdd.' to ignore all hdd metrics) or just the BytesRead metric ('.BytesRead').

Also, the old metrics will still match (so 'platform1.mysql.sda1.BytesRead' will only match that metric)