Added new Maritime Decision Aid Toolbox to Repo

This toolbox contains 4 tools and 1 supporting script called
"SubSpecs.py". The tools include: Find Submarine Canyons, Sub Depth
Restriction Analysis, Farthest on Circle, and Visibility Range at Sea.
The SubSpecs.py is basically is an empty script, but contained in the
"Maritime Decision Aid Toolbox" there is a "script" item which uses
python validation under "validation" tab.
Update TBX description for Publishable Task Tools
Merge pull request #31 from mfunk/master

Updated Publishable Tasks Description