upgrade mockito to the latest available version

pom.xml

@@ -59,7 +59,7 @@
 
     <jgit.version>4.5.2.201704071617-r</jgit.version>
     <junit.version>4.12</junit.version>
-    <mockito.version>2.0.35-beta</mockito.version>
+    <mockito.version>2.8.47</mockito.version>
 
     <fest-assert.version>1.4</fest-assert.version>
   </properties>

src/test/java/org/mockito/internal/util/reflection/Whitebox.java

@@ -0,0 +1,40 @@
+package org.mockito.internal.util.reflection;
+
+import java.lang.reflect.Field;
+
+@Deprecated
+public class Whitebox {
+    public static void setInternalState(Object target, String field, Object value) {
+        Class<?> c = target.getClass();
+        try {
+            Field f = getFieldFromHierarchy(c, field);
+            f.setAccessible(true);
+            f.set(target, value);
+        } catch (Exception e) {
+            throw new RuntimeException("Unable to set internal state on a private field. Please report to mockito mailing list.", e);
+        }
+    }
+
+    private static Field getFieldFromHierarchy(Class<?> clazz, String field) {
+        Field f = getField(clazz, field);
+        while (f == null && clazz != Object.class) {
+            clazz = clazz.getSuperclass();
+            f = getField(clazz, field);
+        }
+        if (f == null) {
+            throw new RuntimeException(
+                    "You want me to get this field: '" + field +
+                    "' on this class: '" + clazz.getSimpleName() + 
+                    "' but this field is not declared withing hierarchy of this class!");
+        }
+        return f;
+    }
+
+    private static Field getField(Class<?> clazz, String field) {
+        try {
+            return clazz.getDeclaredField(field);
+        } catch (NoSuchFieldException e) {
+            return null;
+        }
+    }
+}