Parameterize `naicreport at-a-glance`

[lars-t-hansen]

This module has a number if hardcoded parameters:

• the sampling interval is hardcoded to 4 minutes, this is an outright bug since this is wrong everywhere (#355)
• the intervals for "recent" and "longer" are hardcoded to 30m and 12h respectively, this is ok-ish but in principle wrong since esp the "recent" cutoff depends on the sampling interval and this can be longer than the 5 minutes we use on MLX/Fox, notably on Saga it is currently 15 or 30 minutes, also see #291
• the interval for "long" (the window for violators and zombies) is hardcoded to 24h, this is probably OK as a default but it doesn't seem meaningful to hide it

[lars-t-hansen]

The sampling interval was made a parameter in #355, awaiting some results.

[lars-t-hansen]

The sampling interval was made a parameter in #355, awaiting some results.

Actually this was for the --with-uptime parameter of naicreport load (which was also broken), not for the parameter of at-a-glance. Sigh.

While I'm here: currently we treat this parameter as cluster-wide. This need not be so: it may be that the sampling interval should be shorter on interactive and login nodes. The sampling interval is really per-node. (And of course, the node knows best what the interval is, it shouldn't have to be configured in multiple places. So really it should be transmitted from the node with the sonar data.)

[lars-t-hansen]

What remains here for the time being is low priority.