Restarts KingTest with testMoves
Satisfies KingTest::testMoves
Adds assertions to KingTest::testMoves for edge of board
Just moving protected function to bottom of class
Filter check moves

Filters out moves that leave or put the King into check from the possible
moves on each piece.

I know ... I broke the rules of TDD. I wish I would have been patient
enough to see how I would do this the right way. Part of me feels that
sometimes it's easier to just implement, figure out what tests are missing
to get 100% coverage, then fill them in.
Moves tests into subdirectory

I'm planning on adding a PieceTestCase with an assertMoves() method. Need
to separate from tests into an autoloadable directory within the test
folder.
Adds PieceTestCase with assertMoves() Yay!

+ Updates composer.json to autoload out of test/classes
Adds assertion to KingTest::testMoves to reach 100% coverage

+ King cannot move into check
Adds optional parameter to provide more meaningful message to assertMoves
Updates PieceTestCase->assertMoves to accept expected count
Refactor tests to use PieceTestCase->assertMoves

Ugh. Should have thought of this before all that.
Update TODO.md
Adds PieceTest::testCheckmate
Satisfies PieceTest::testCheckmate
Updates README.md

Knowing how to view coverage reports is important.