IntelliJ project configuration: convert JUnit4 to repository library

.idea/libraries/JUnit4.xml

@@ -1,16 +1,16 @@
 <component name="libraryTable">
-  <library name="JUnit4">
+  <library name="JUnit4" type="repository">
+    <properties maven-id="junit:junit:4.12"/>
     <ANNOTATIONS>
       <root url="file://$PROJECT_DIR$/lib/annotations/junit4"/>
     </ANNOTATIONS>
     <CLASSES>
-      <root url="jar://$PROJECT_DIR$/lib/hamcrest-core-1.3.jar!/" />
-      <root url="jar://$PROJECT_DIR$/lib/junit-4.12.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/junit/junit/4.12/junit-4.12.jar!/"/>
+      <root url="jar://$MAVEN_REPOSITORY$/org/hamcrest/hamcrest-core/1.3/hamcrest-core-1.3.jar!/"/>
     </CLASSES>
-    <JAVADOC />
+    <JAVADOC/>
     <SOURCES>
-      <root url="jar://$PROJECT_DIR$/lib/src/hamcrest-1.3-src.zip!/hamcrest-core/src/main/java" />
-      <root url="jar://$PROJECT_DIR$/lib/src/junit-4.12-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/junit/junit/4.12/junit-4.12-sources.jar!/"/>
     </SOURCES>
   </library>
 </component>

README.md

@@ -1,6 +1,6 @@
 # IntelliJ IDEA Community Edition
 ### Building and Running from the IDE
-To develop IntelliJ IDEA, you can use either IntelliJ IDEA Community Edition or IntelliJ IDEA Ultimate not older than 2017.1. To build and run the code:
+To develop IntelliJ IDEA, you can use either IntelliJ IDEA Community Edition or IntelliJ IDEA Ultimate not older than 2017.2.1. To build and run the code:
 * Run **getPlugins.sh** / **getPlugins.bat** from the project root directory to check out additional modules.
 * If this git repository is not on 'master' branch you need to checkout the same branches/tags in android and android/tools-base git repositories.
 * Open the project.