- Scriptcontext debugged to be working

- Added a drivable adapter to scriptcontext nodes
- Added subsampling to simulated histograms (and as a general option) in
  order to support Gumtree testing.

devser.c

@@ -60,7 +60,9 @@ static void DevFreeActionList(DevAction *actions) {
 }
 
 static void DevKillTask(void *devser) {
-  free(devser);
+	if(devser != NULL){
+		DevKill(devser);
+	}
 }
 
 DevAction *DevNextAction(DevSer *devser) {
@@ -119,14 +121,17 @@ int DevQueueTask(void *ds) {
     status = AsconTask(devser->asyncConn);
     if (status == AsconFailure) {
       devser->errmsg = AsconGetErrList(devser->asyncConn);
-      return 1;
     } else if (status != AsconReady) {
       return 1;
     }
     if (devser->steps > 0) { /* debugging mode */
       devser->steps--;
     }
-    replyData = AsconRead(devser->asyncConn);
+    if(status == AsconFailure){
+    	replyData = devser->errmsg->text;
+    } else {
+    	replyData = AsconRead(devser->asyncConn);
+    }
     sendData = action->hdl(action->data, replyData);
     if (sendData != NULL) {
       AsconWrite(devser->asyncConn, sendData, 0);
@@ -144,8 +149,8 @@ int DevQueueTask(void *ds) {
 }
 
 DevSer *DevMake(SConnection *con, int argc, char *argv[]) {
-  DevSer *devser;
-  Ascon *asyncConn;
+  DevSer *devser = NULL;
+  Ascon *asyncConn = NULL;
   
   asyncConn = AsconMake(con, argc, argv);
   if (!asyncConn) {