Add Solver class.

src/pegp/solver.d

@@ -0,0 +1,17 @@
+module pegp.solver;
+
+import pegp.board;
+
+class Solver
+{
+    Board m_board;
+
+    this(int size)
+    {
+        m_board = new Board(size);
+    }
+
+    static void solve()
+    {
+    }
+}