Integrate serialization plugin into big Kotlin plugin

Split import handlers into multiple files
Add empty Maven handler for Android Studio

Add testRuntime dependency on kx-serialization-plugin for all modules which require compiler
plugins in test classpath

libraries/tools/kotlin-maven-serialization/pom.xml

@@ -16,10 +16,16 @@
         <kotlin.version>1.2-SNAPSHOT</kotlin.version>
     </properties>
 
-    <groupId>org.jetbrains.kotlinx</groupId>
+    <parent>
+        <groupId>org.jetbrains.kotlin</groupId>
+        <artifactId>kotlin-project</artifactId>
+        <version>1.3-SNAPSHOT</version>
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+
     <artifactId>kotlinx-maven-serialization-plugin</artifactId>
     <packaging>jar</packaging>
-    <version>0.7.0-eap-1</version>
+
     <description>Serialization plugin for Maven</description>
 
     <repositories>
@@ -138,14 +144,4 @@
             </plugin>
         </plugins>
     </build>
-
-
-    <distributionManagement>
-        <repository>
-            <id>bintray-repo</id>
-            <url>https://api.bintray.com/maven/kotlin/kotlinx/kotlinx.serialization.plugin/</url>
-        </repository>
-    </distributionManagement>
-
-
 </project>