Different approach to starting proxy

appveyor.yml

 version: 1.1.{build}
 image: Visual Studio 2015
-configuration: Debug
+configuration: Debug
+install:
+  - cmd: python --version
+    
+  - cmd: netsh advfirewall firewall add rule name="Python 2.7" dir=in action=allow program="C:\Python27\python.exe" enable=yes
+
+  - cmd: netsh advfirewall firewall add rule name="Open Port 1883" dir=in action=allow protocol=TCP localport=1883
+
+  - cmd: netsh advfirewall set allprofiles state off
+    
+  - ps: Start-Process python ..\test\mqttsas2.py mqtt.iotree.co.uk
+  
 build_script:
 - cmd: >-
     mkdir build.paho
@@ -11,18 +22,7 @@ build_script:
 
     cmake -G "NMake Makefiles" -DPAHO_WITH_SSL=TRUE -DPAHO_BUILD_DOCUMENTATION=FALSE -DPAHO_BUILD_SAMPLES=TRUE -DCMAKE_BUILD_TYPE=Release -DCMAKE_VERBOSE_MAKEFILE=TRUE ..
 
-    nmake
-
-    python --version
-
-
-    netsh advfirewall firewall add rule name="Python 2.7" dir=in action=allow program="C:\Python27\python.exe" enable=yes
-
-    netsh advfirewall firewall add rule name="Open Port 1883" dir=in action=allow protocol=TCP localport=1883
-
-    netsh advfirewall set allprofiles state off
-
-    start /B python ..\test\mqttsas2.py mqtt.iotree.co.uk
+    nmake
 
     ctest -T test -VV