Experimental regridding enhancements
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Bilinear and area weighted regridding functions are now available in :mod:`iris.experimental.regrid`. The final API is still in development, but in the meantime :func:`regrid_bilinear_rectilinear_src_and_grid`  can be used to regrid a cube onto a horizontal grid defined in a different coordinate system. The data values are calculated using bilinear interpolation. :func:`regrid_area_weighted_rectilinear_src_and_grid` can be used to regrid a cube such that the data values of the resulting cube are calculated using the area weighted mean. Both of these function support masked data and handle derived coordinates such as hybrid height.