assertJ 3.2.0

Reasons:
1) fixed: Path's assertions should not rely on java.nio.Path.toFile()
2) kotlin 0.13 is compatible, no more compilation error due to ambigous assertThat resolution (or it was not kotlin issue, but "Reintroduce Assertions providing all AssertJ methods - in case of ambigous assertThat resolution, use either AssertionsForInterfaceTypes or AssertionsForClassTypes.")

.idea/libraries/assertJ.xml

@@ -1,13 +1,13 @@
 <component name="libraryTable">
   <library name="assertJ">
     <CLASSES>
-      <root url="jar://$PROJECT_DIR$/lib/dev/assertj-core-2.1.0.jar!/" />
+      <root url="jar://$PROJECT_DIR$/lib/dev/assertj-core-3.2.0.jar!/" />
     </CLASSES>
     <JAVADOC>
-      <root url="jar://$PROJECT_DIR$/lib/dev/assertj-core-2.1.0-javadoc.jar!/" />
+      <root url="jar://$PROJECT_DIR$/lib/dev/assertj-core-3.2.0-javadoc.jar!/" />
     </JAVADOC>
     <SOURCES>
-      <root url="jar://$PROJECT_DIR$/lib/dev/assertj-core-2.1.0-sources.jar!/" />
+      <root url="jar://$PROJECT_DIR$/lib/dev/assertj-core-3.2.0-sources.jar!/" />
     </SOURCES>
   </library>
 </component>