Use protobuf with renamed packages, pack to IDEA plugin

Update GenerateProtoBuf.kt to also regexp-replace com.google.protobuf with
org.jetbrains.kotlin.protobuf in generated Java sources

 #KT-12581 Fixed

ultimate/.idea/libraries/protobuf.xml

@@ -0,0 +1,11 @@
+<component name="libraryTable">
+  <library name="protobuf">
+    <CLASSES>
+      <root url="jar://$PROJECT_DIR$/../dependencies/protobuf-2.5.0.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES>
+      <root url="jar://$PROJECT_DIR$/../dependencies/protobuf-2.5.0-sources.jar!/" />
+    </SOURCES>
+  </library>
+</component>

ultimate/kotlin-ultimate.iml

@@ -28,5 +28,6 @@
     <orderEntry type="library" scope="PROVIDED" name="diagram-support" level="project" />
     <orderEntry type="library" scope="PROVIDED" name="intellij-core" level="project" />
     <orderEntry type="library" name="idea-full" level="project" />
+    <orderEntry type="library" name="protobuf" level="project" />
   </component>
 </module>