mitiff writer add config option to add or not to add the size of a pixel in the proj string

[TAlonglong]

Feature Request

When plotting geotiff and mitiff images from the same satellite, different products, I see the geo location differs.

mitiff with the current correction

geotiff

Looking in the code I see I add the size of a pixel to the lower left corner of the proj4 string fort DIANA to plot the data correctly.

For some reasons I don't understand now, this apparently is not correct any more.

I want to add a config option to turn off this correction.

I don't think there are any other users of this writer, but to be sure I want to keep the current correction the default.

[djhoese]

Since this effects a single writer I would suggest this be done as a keyword argument. I assume by "config option" you meant satpy.config.