Change target API to 29, and enable requestLegacyExternalStorage so that

phones running android 11 (and 10?) can access /sdcard without using
'scoped storage'.  NB - when google play forces us to use API 30 (later
this year?), will need to switch to new MANAGE_EXTERNA_STORAGE
permission.

app/build.gradle

@@ -25,7 +25,7 @@ android {
     defaultConfig {
         applicationId "org.galexander.sshd"
         minSdkVersion 17
-        targetSdkVersion 30
+        targetSdkVersion 29
 
         versionCode 26
         versionName "26"

app/src/main/AndroidManifest.xml

@@ -10,7 +10,8 @@
     <uses-feature android:name="android.hardware.touchscreen" android:required="false" />
     <application android:label="SimpleSSHD" android:icon="@drawable/icon"
 	  android:allowBackup="false" android:banner="@drawable/tvbanner"
-	  android:usesCleartextTraffic="true">
+	  android:usesCleartextTraffic="true"
+	  android:requestLegacyExternalStorage="true">
         <activity android:name="SimpleSSHD" android:label="SimpleSSHD"
 	    android:launchMode="singleTask">
             <intent-filter>