check for existing swipe handlers

apps/backswipe/ChangeLog

@@ -1 +1,2 @@
 0.01: New App!
+0.02: Don't fire if the app uses swipes already.

apps/backswipe/boot.js

@@ -15,8 +15,8 @@
 
     var currentFile = global.__FILE__ || "";
 
-    if(global.BACK) delete global.BACK;
-    if (options && options.back && enabledForApp(currentFile)) {
+    if (global.BACK) delete global.BACK;
+    if (options && options.back && enabledForApp(currentFile) && (Bangle["#onswipe"] instanceof Array)&&Bangle["#onswipe"].length>1 ) {
       global.BACK = options.back;
     }
     setUI(mode, cb);

apps/backswipe/metadata.json

@@ -1,7 +1,7 @@
 { "id": "backswipe",
   "name": "Back Swipe",
   "shortName":"BackSwipe",
-  "version":"0.01",
+  "version":"0.02",
   "description": "Service that allows you to use an app's back button using left to right swipe gesture",
   "icon": "app.png",
   "tags": "back,gesture,swipe",