LogService: add setLevel method to public API

Specifically, the setLevel(String classOrPackageName, int level) method
was public in AbstractLogService, but not part of the LogService API.

Author: ctrueden

src/main/java/org/scijava/log/AbstractLogService.java

@@ -251,7 +251,7 @@ public void setLevel(final int level) {
 		currentLevel = level;
 	}
 
-//	@Override
+	@Override
 	public void setLevel(final String classOrPackageName, final int level) {
 		classAndPackageLevels.put(classOrPackageName, level);
 	}

src/main/java/org/scijava/log/LogService.java

@@ -100,4 +100,6 @@ public interface LogService extends SciJavaService {
 
 	void setLevel(int level);
 
+	void setLevel(String classOrPackageName, int level);
+
 }