WIP Testing meca -I to place symbols in a legend or box #4449
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Description of proposed changes
See #4445. This PR tests this concept. For example you can try this command and change the -I choices:
echo -159.70 54.81 39 0.82 -0.68 -0.14 0.63 0.34 -0.40 25 | gmt meca -R0/10/0/5 -Jx1c -B0 -Sm2.5c -M -G110/168/255 -T0 -W0.5p -IjTR+o0.25c -png mapFew things to know:
We should make a test page of all the 9 meca symbols using the 9 adjustment points.