Merge branch 'develop-AnimVSLTime' into 'master'

Develop anim vsl time

Hi,

   In the branch, I have put the AnimVsLTime function which relies now on PlotEquiMap and PlotStereoMap as requested. This function creates a gif animation that can be uploaded either in a web browser or in a ppt to visualize it. What is animated can be the
full values or anomalies of a forecast, the climatology or any skill score. I have added an example in the documentation that gives an idea of the applications this function can have. @lpcaron, @cprodhomme, @eexarchou, @obellprat, would you mind testing it, please ?

  If I am not available anymore to fix a bug, LP would take care of correcting it.

Best regards
Virginie

See merge request !42