Samples: add sample Android app

Author: lhoward

Package.swift

@@ -246,6 +246,9 @@ let package = Package(
         .linkedLibrary(
           "jvm",
           .when(platforms: [.iOS, .macOS, .tvOS, .watchOS, .macCatalyst, .linux, .openbsd, .wasi, .windows])),
+        .linkedLibrary(
+          "nativehelper",
+          .when(platforms: [.android])),
       ]
     ),
     .target(

Samples/JavaKitSampleApp/Sources/JavaKitAndroidExample/.gitignore

@@ -0,0 +1,15 @@
+*.iml
+.gradle
+/local.properties
+/.idea/caches
+/.idea/libraries
+/.idea/modules.xml
+/.idea/workspace.xml
+/.idea/navEditor.xml
+/.idea/assetWizardSettings.xml
+.DS_Store
+/build
+/captures
+.externalNativeBuild
+.cxx
+local.properties