cyclone wind speed units

[gubuntu]

problem

cyclone legend shows mph

Mozambique is metric and wants kph instead.

solution

confirm what the values actually represent from the documentation (are they really mph in the first place?)

convert legend labels to kph

update InaSAFE keywords to properly use the raster values if they represent mph

[NyakudyaA]

@gubuntu this layer had no metadata when I looked at it. The mph was a unit that I settled for after looking at the majority of rasters depicting cyclone.

@raisserafael can you please provide me with the correct metadata definitions for these layers. If they are really in kph changing the metadata should be basically easy as it just involves updating the layers with kph