[fieldNameConstants] code review, docs, tests, fixup.

test/transform/resource/before/FieldNameConstantsBasic.java

@@ -0,0 +1,11 @@
+import lombok.experimental.FieldNameConstants;
+import lombok.AccessLevel;
+
+@FieldNameConstants
+public class FieldNameConstantsBasic {
+	@FieldNameConstants(level = AccessLevel.PROTECTED)
+	String iAmADvdPlayer;
+	int $skipMe;
+	static double skipMeToo;
+	String butPrintMePlease;
+}