SMTs ctors visibility

Some of the SMTs introduced recently had the ctor visibility set to protected.

pom.xml

@@ -26,7 +26,7 @@
 
     <groupId>io.lenses</groupId>
     <artifactId>kafka-connect-smt</artifactId>
-    <version>1.1.0-SNAPSHOT</version>
+    <version>1.1.1-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <properties>

src/main/java/io/lenses/connect/smt/header/InsertRecordTimestampHeaders.java

@@ -23,7 +23,7 @@
 public class InsertRecordTimestampHeaders<R extends ConnectRecord<R>>
     extends InsertTimestampHeaders<R> {
 
-  protected InsertRecordTimestampHeaders() {
+  public InsertRecordTimestampHeaders() {
     super(InsertRecordTimestampHeaders.CONFIG_DEF);
   }
 

src/main/java/io/lenses/connect/smt/header/InsertRollingTimestampHeaders.java

@@ -45,7 +45,7 @@ abstract class InsertRollingTimestampHeaders<R extends ConnectRecord<R>>
               "The rolling window type. The allowed values are hours, minutes or seconds.");
   private RollingWindowDetails rollingWindowDetails;
 
-  protected InsertRollingTimestampHeaders() {
+  public InsertRollingTimestampHeaders() {
     super(CONFIG_DEF);
   }
 

src/main/java/io/lenses/connect/smt/header/InsertRollingWallclockHeaders.java

@@ -26,6 +26,10 @@ class InsertRollingWallclockHeaders<R extends ConnectRecord<R>>
 
   private Supplier<Instant> supplier = Instant::now;
 
+  public InsertRollingWallclockHeaders() {
+    super();
+  }
+
   // used solely for testing purposes
   void setInstantSupplier(Supplier<Instant> supplier) {
     this.supplier = supplier;

src/main/java/io/lenses/connect/smt/header/InsertWallclockHeaders.java

@@ -24,7 +24,7 @@
 public class InsertWallclockHeaders<R extends ConnectRecord<R>> extends InsertTimestampHeaders<R> {
   private Supplier<Instant> instantSupplier = Instant::now;
 
-  protected InsertWallclockHeaders() {
+  public InsertWallclockHeaders() {
     super(InsertTimestampHeaders.CONFIG_DEF);
   }