begin support for showing/sharing qr codes for channel settings

app/src/main/AndroidManifest.xml

@@ -87,6 +87,23 @@
 
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
+
+            <!-- The QR codes to share channel settings are shared as meshtastic URLS
+
+            an approximate example:
+            http://www.meshtastic.org/s/YXNkZnF3ZXJhc2RmcXdlcmFzZGZxd2Vy
+            -->
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+
+                <data
+                    android:scheme="http"
+                    android:host="www.meshtastic.org"
+                    android:pathPrefix="/s" />
+            </intent-filter>
         </activity>
 
         <receiver android:name="com.geeksville.mesh.service.BootCompleteReceiver">

app/src/main/aidl/com/geeksville/mesh/IMeshService.aidl

@@ -32,6 +32,14 @@ interface IMeshService {
     */
     NodeInfo[] getNodes();
 
+    /// This method is only intended for use in our GUI, so the user can set radio options
+    /// It returns a RadioConfig protobuf.
+    byte []getRadioConfig();
+
+    /// This method is only intended for use in our GUI, so the user can set radio options
+    /// It sets a RadioConfig protobuf
+    void setRadioConfig(in byte []payload);
+
     /**
     Is the packet radio currently connected to the phone?
     */

app/src/main/java/com/geeksville/mesh/service/MeshService.kt

@@ -541,6 +541,14 @@ class MeshService : Service(), Logging {
                 })
             }
 
+        override fun getRadioConfig(): ByteArray = toRemoteExceptions {
+            return connectedRadio.readRadioConfig()
+        }
+
+        override fun setRadioConfig(payload: ByteArray) = toRemoteExceptions {
+            connectedRadio.writeRadioConfig(payload)
+        }
+
         override fun getNodes(): Array<NodeInfo> = toRemoteExceptions {
             val r = nodeDBbyID.values.toTypedArray()
             info("in getOnline, count=${r.size}")

app/src/main/proto/mesh.options

@@ -16,6 +16,7 @@
 
 # 128 bit psk key (we don't use 256 bit yet because we want to keep our QR code small)
 *ChannelSettings.psk max_size:16 fixed_length:true
+*ChannelSettings.name max_size:12
 
 # MyMessage.name         max_size:40 
 # or fixed_length or fixed_count, or max_count

app/src/main/proto/mesh.proto

@@ -171,6 +171,9 @@ message ChannelSettings {
     /// A simple preshared key for now for crypto.  At first I'm using 128 bit (16 byte) block for the Speck crypto
     /// but for beta we'll want something more carefully thought through.  I want to keep the QR code small
     bytes psk = 4;
+
+    /// A SHORT name that will be packed into the URL.  Less than 12 bytes.  Something for end users to call the channel
+    string name = 5;
 }
 
 // The entire set of user settable/readable settings for our radio device.  Includes both the current channel settings