create migration script for old data

androidExportReader/build.gradle

@@ -0,0 +1,47 @@
+
+buildscript {
+    repositories {
+        gradlePluginPortal()
+    }
+    dependencies {
+        classpath 'gradle.plugin.com.github.johnrengelman:shadow:7.1.2'
+    }
+}
+
+plugins {
+    id 'java'
+    id("com.github.johnrengelman.shadow") version "7.1.2"
+    id 'application'
+}
+
+group 'com.blackforestbytes'
+version '1.0-SNAPSHOT'
+
+repositories {
+    mavenCentral()
+    maven { url "https://jitpack.io" }
+}
+
+application {
+    mainClass = 'com.blackforestbytes.Main'
+}
+
+jar {
+    manifest {
+        attributes 'Main-Class': application.mainClass
+    }
+}
+
+tasks.jar {
+    manifest.attributes["Main-Class"] = application.mainClass
+}
+
+dependencies {
+    implementation 'com.github.RalleYTN:SimpleJSON:2.1.1'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.1'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.1'
+}
+
+test {
+    useJUnitPlatform()
+}