Reintroduce 5.2.0 Release Notes summary

Author: sbrannen

documentation/src/docs/asciidoc/release-notes/index.adoc

@@ -7,7 +7,7 @@ Stefan Bechtold; Sam Brannen; Johannes Link; Matthias Merdes; Marc Philipp; Chri
 :numbered!:
 //
 
-This document contains the _change log_ for all JUnit 5 releases since 5.3 GA.
+This document contains the _change log_ for all JUnit 5 releases since 5.2 GA.
 
 Please refer to the <<../user-guide/index.adoc#user-guide,User Guide>> for comprehensive
 reference documentation for programmers writing tests, extension authors, and engine
@@ -18,3 +18,5 @@ include::../link-attributes.adoc[]
 include::release-notes-5.3.1.adoc[]
 
 include::release-notes-5.3.0.adoc[]
+
+include::release-notes-5.2.0.adoc[]

documentation/src/docs/asciidoc/release-notes/release-notes-5.2.0.adoc

@@ -0,0 +1,12 @@
+[[release-notes-5.2.0]]
+== 5.2.0
+
+*Date of Release:* April 29, 2018
+
+*Scope:* JUnit BOM, support for Maven Surefire 2.21.0 allowing builds with Java 9 and
+Java 10, _argument aggregation_ and _widening primitive conversion_ for arguments in
+parameterized tests, external factory methods for `@MethodSource`, as well as various
+minor improvements and bug fixes.
+
+For complete details consult the
+https://junit.org/junit5/docs/5.2.0/release-notes/index.html[5.2.0 Release Notes] online.