Added Corner Black

Rule image
Added some rule set presentations and proofs
Fixed a bug where the code directory was declared incorrectly which caused adding the project to eclipse to break
Merge pull request #57 from Bram28/build.xml_bugfix

Build.xml fix
Added the Masuy presentation to Rules

Added 2 sample nurikabe proofs showing moves that should check out
Added Battleship Powerpoint
Fixed the slowdown caused by merge
This commit fixes the "Black must connect" bug
Closes #61 and closes #54"
This commit fixes the "Black must connect" bug
Closes #60 and closes #54"
Merge branch 'master' of https://github.com/Bram28/LEGUP
Revert "Added Corner Black"

This reverts commit ea7ef9bb671ae4d5d5aeee2f8c710325e725d21b.
Revert "Revert "Added Corner Black""

This reverts commit 906170854ab6c422007db0844cb18ea1a99a9f27.
Updated CornerBlack

updated the corner black nurikabe rule icon
Added check for external black square in contradiction
Also, added proof that shows serious slowdown in nurikabe
Merge branch 'master' of https://github.com/Bram28/LEGUP
Linked to the new Corner Black icon

Deleted some old proofs that couldn't load anymore

Added some new proofs to show which icons still show up and which do
not.

Also added a complete proof of the one Nurikabe puzzle
Fixed justification icons not displaying after loading proof

Changed getImageName method in Justification to abstract
Implemented method in all subclasses of Justification