Ignore clear outliers on rendering the graph

[theking2]

If for whatever reason a candidate has persistant difficulty reaching the server it pushes the right axis in such a way that the graph is less informative.

this prompt should do it.

• Allow a threshold below which candidates are ignored in the graph.
• Mark the candidate in the list as not being graphed.
• THe threshold can be a predefined configuration value or mathematical 5% confidence cut off.

https://community.ntppool.org/t/twtpe3-2kg9ezv-100-for-days-on-end/4246/4