align country and basin raster map boundaries to stop creating filler land units

[aldivi]

it appears that there are only 384 valid land regionXglu land units, but moirai describes 397 (and in some cases GCAM may output 392?). The extra ones are caused by slight misalignment in the raster maps of basins and countries. Along these boundaries a few pixels are created that fall into two additional units (c1Xg2 and c2Xg1), where only the main two units should exist (c1Xg1 and c2Xg2).

Also change the batch of pixels in Namibia that is assigned to South Africa (Walvis Bay), to Namibia. Some older data must have slipped in here to cause this.

[aldivi]

The five units that are dropped by gcam are: malta (eu-12 med sea isl 12063), madagascar (southeast asia madagascar 29177), st. pierre and miquelon (eu-15 atl oc seabrd 13019, french), turks and caicos isl (eu-15 carribean 13101, british), and melilla (eu-15 med sea south cst 13080, spain). The small islands/areas are fairly far from their ruling bodies, but madagascar I guess just isn't used (lack of data?).

The eight mismatched boundary units are output by GCAM.