Links in help and about are clickable. Also added scroll in about activity. Fixes #232.

src/main/java/de/dennisguse/opentracks/AboutActivity.java

@@ -2,11 +2,13 @@ package de.dennisguse.opentracks;
 
 import android.os.Bundle;
 import android.view.Menu;
+import android.view.ViewGroup;
 import android.widget.TextView;
 
 import androidx.annotation.Nullable;
 
 import de.dennisguse.opentracks.util.SystemUtils;
+import de.dennisguse.opentracks.util.ViewUtils;
 
 public class AboutActivity extends AbstractActivity {
 
@@ -27,6 +29,8 @@ public class AboutActivity extends AbstractActivity {
 
         TextView textURL = findViewById(R.id.about_app_url);
         textURL.setText(getString(R.string.about_url, getString(R.string.app_web_url)));
+
+        ViewUtils.makeClickableLinks((ViewGroup) findViewById(android.R.id.content));
     }
 
     protected int getLayoutResId() {