Display a generation-duration for each facility and fuel_tech (by region)

[simonhac]

A generation-duration chart shows the a chart of the proportion of time (over a period) a generator has been above given power levels.

We should compute and display generation-duration chart for each facility and each fuel_tech over for each region. The data computed should include:

• the capacity factor (average generation / nominal capacity)
• the service factor (proportion of time that power has been > 0 MW)

Here's an example that @dylanjmcconnell made for Waubra Wind Farm a few years back:

[simonhac]

Not sure over what period. Last 12 months? Each year? Financial year? User defined period?

Could start with last 12 months, computed monthly?