Updated Version History

Version history in anti-chronological order.

Merge branch 'fix/v0.7.2'

Merge branch 'rel/v0.7.1'

Merge branch 'rel/v0.7'

Optional night-time shading and Julian time in plots

Amending Julia plotting routines in jl.mod/make_plots.jl to allow
optional night-time shading and different time formats (model time
starting at 0 or Julian time, i.e. date/time of the year).
In make_plots, new subroutine night_shade to find the boundaries of all
nights for shading.