apps: Add GPSD app.

Once enabled, running a GPSD client (for example, cgps) on the node can obtain the current position and motion information of the node.

Change-Id: Ib88424cc7fe07898de5b37c1699e170bf89e58a5
diff --git a/minindn/wifi/minindnwifi.py b/minindn/wifi/minindnwifi.py
index 8eb9b2c..6a6ad88 100644
--- a/minindn/wifi/minindnwifi.py
+++ b/minindn/wifi/minindnwifi.py
@@ -411,7 +411,7 @@
                         continue
                     key = param.split('=')[0]
                     value = param.split('=')[1]
-                    if key in ['range']:
+                    if key in ['range', 'min_v', 'max_v']:
                         value = int(value)
                     params[key] = value
             # ip6 address for each station using id