Switch libraries to AndroidX

+# 2.0.0
+* Breaking change: Switch libraries to AndroidX
+
 # 1.3.5
 * Restore compatibility with Flutter 1.0.0
 * Update code to Dart 2.1.0

@@ -16,6 +16,6 @@
 
 package net.nfet.flutter.printing;
 
-import android.support.v4.content.FileProvider;
+import androidx.core.content.FileProvider;
 
 public class PrintFileProvider extends FileProvider {}

@@ -32,7 +32,7 @@ import android.print.PrintDocumentAdapter;
 import android.print.PrintDocumentInfo;
 import android.print.PrintManager;
 import android.print.pdf.PrintedPdfDocument;
-import android.support.v4.content.FileProvider;
+import androidx.core.content.FileProvider;
 
 import java.io.File;
 import java.io.FileOutputStream;

@@ -38,7 +38,7 @@ android {
         targetSdkVersion 28
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
 
     buildTypes {
@@ -56,6 +56,6 @@ flutter {
 
 dependencies {
     testImplementation 'junit:junit:4.12'
-    androidTestImplementation 'com.android.support.test:runner:1.0.2'
-    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
+    androidTestImplementation 'androidx.test:runner:1.1.1'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
 }

@@ -5,7 +5,7 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.2.1'
+        classpath 'com.android.tools.build:gradle:3.3.1'
     }
 }
 

 org.gradle.jvmargs=-Xmx1536M
+android.useAndroidX=true
+android.enableJetifier=true