The SMET specification has been changed and brought to version 1.1. The units_multiplier and units_offset order has been changed: now, the multiplier is applied FIRST and then the offset. This allows to disable a SMET column by setting the mutiplier to 0 and the offset to nodata. A warning is displayed by SMETIO for all files version <1.1 urging users to check their files and update them to 1.1.

Code cleanup in IMISIO, grid constraint for wind that it must be greater than 0 in Meteo2DInterpolator.