Resolve "Fix time projection of StackInspector"

Issues: Closes #593 (closed)

This fixes two of the three issues highlighted by @mreininghaus in #593 (closed), that the ETA actually works and that a correction is applied to ignore overhead time (such as building the proposal tables).

The first an issue in the way that std::put_time is overloaded but could be resolved by forcing a type.

The second issue was resolved by re-referencing the "start time" of the simulation to when 2% of the energy was lost. This could probably be set to a lower value, but this will certainly be safe and seemed to at least cover when all the tables are made.

This does NOT fix the issue of forcing the log-level for printing and silencing INFO will still silence the stack inspector. But this might be a larger issue and can be fixed in the future with #565.

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