Statistics

[Sekhy2]

It would be interesting to have a "statistics" option on the menu.

We currently have the max, min and average length of cycle displayed above the calendar.
It would be nice to visualize (in a separate window) more stats about cycles :

• median (for irregular cycles this could make more sense than the mean),
• standard deviation,
• maybe other statistical indicators ?
• maybe a nice plot of length of cycles over time/histogram of cycle length (this is more work)
• data size (e.g. 10 cycles)

Optionally, users could choose "see statistics over the x previous cycles" to have some "recent" statistics.

Thanks!