Idea

To have a list of shorthand to define specific geography region. This way, a map of the Mediterranean Sea (MS) could be get with a code like -R=MS (or -R=MediterraneanSea).

From the [dcw-gmt issue 18].

From Paul's comment:
The implementation of this would be a table of codes for the oceans and a corresponding w e s n. Then the gmtinit_parse_R_option would check if we get one of those (just like we do for -Rg -Rd) and substitute the region.

The regions would have a code/shorthand and long names.

The list should include regions like, oceans, seas, and specific geographic regions (like Balcans, Middle East, Far East, etc.).

I think we should discussed the regions to be included.