Generate copyright year in swagger template code

- exclude generated source code from checkstyle by default

Change-Id: I3f79183a8aae1f24d36558860555b5b0298cd8c3
diff --git a/tools/build/buck-plugin/src/main/java/org/onosproject/onosjar/SwaggerGenerator.java b/tools/build/buck-plugin/src/main/java/org/onosproject/onosjar/SwaggerGenerator.java
index 88850e8..e567c81 100644
--- a/tools/build/buck-plugin/src/main/java/org/onosproject/onosjar/SwaggerGenerator.java
+++ b/tools/build/buck-plugin/src/main/java/org/onosproject/onosjar/SwaggerGenerator.java
@@ -33,6 +33,7 @@
 import java.io.FileWriter;
 import java.io.IOException;
 import java.io.PrintWriter;
+import java.time.Year;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -502,7 +503,9 @@
                 src = src.replace("${api.package}", apiPackage)
                         .replace("${web.context}", webContext)
                         .replace("${api.title}", apiTitle)
-                        .replace("${api.description}", apiDescription);
+                        .replace("${api.description}", apiDescription)
+                        .replace("${year}", Year.now().toString());
+
                 Files.write(src.getBytes(), reg);
             } catch (IOException e) {
                 throw new RuntimeException("Unable to write " + reg, e);