Merge pull request #721 from geeksville/dev

add (editable) android warning landing page

docs/software/android-too-old.md

@@ -0,0 +1,11 @@
+# Your android application needs updating
+
+Hi.
+
+If you've landed here that means your android application is too old for the running device firmware.  Usually our updates are backwards compatible, but in this special circumstance it is not.  Sorry.
+
+Probably, what this means is that you installed the **alpha test** version of the firmware from github.  We really love people helping with development by running the alpha test binaries.  But if you aren't ready to sign up for that right now, please go back to [github](https://github.com/meshtastic/Meshtastic-device/releases) and install the latest **not alpha** 1.1.x firmware.
+
+If you **do** intend to run the alpha test please opt-in to receive the alpha test version of the android application.
+
+If you have problems/questions please post in our [forum](https://meshtastic.discourse.group) and some nice person will probably help.