Address IntelliJ warnings

This commit addresses a large number of IntelliJ warnings
that have been left hanging around for far too long.

src/main/java/com/loomcom/symon/jterminal/bell/BellStrategy.java

@@ -31,7 +31,7 @@ public interface BellStrategy {
 	/**
 	 * Sounds the bell.
 	 */
-	public void soundBell();
+	void soundBell();
 
 }