Prepare pmd release 6.17.0

docs/_config.yml

@@ -3,7 +3,7 @@ repository: pmd/pmd
 pmd:
     version: 6.17.0
     previous_version: 6.16.0
-    date: ??-July-2019
+    date: 28-July-2019
     release_type: minor
 
 # release types: major, minor, bugfix

docs/pages/next_major_development.md

@@ -73,6 +73,10 @@ the breaking API changes will be performed in 7.0.0.
 an API is tagged as `@Deprecated` or not in the latest minor release. During the development of 7.0.0,
 we may decide to remove some APIs that were not tagged as deprecated, though we'll try to avoid it." %}
 
+#### 6.17.0
+
+No changes.
+
 #### 6.16.0
 
 ##### Deprecated APIs

docs/pages/release_notes.md

@@ -62,8 +62,6 @@ Being based on a proper Antlr grammar, CPD can:
 *   xml
     *   [#1666](https://github.com/pmd/pmd/issues/1666): \[xml] wrong cdata rule description and examples
 
-### API Changes
-
 ### External Contributions
 
 *   [#1869](https://github.com/pmd/pmd/pull/1869): \[xml] fix #1666 wrong cdata rule description and examples - [Artem](https://github.com/KroArtem)