updated pip3 cmd in aws demo

faafo/contrib/install-aws.sh

@@ -155,14 +155,14 @@ if [[ -e /etc/os-release ]]; then
         git clone https://gogs.informatik.hs-fulda.de/srieger/cloud-computing-msc-ai-examples
         cd cloud-computing-msc-ai-examples/faafo
         # following line required by bug 1636150
-        sudo pip install --upgrade pbr
+        sudo pip3 install --upgrade pbr
         # in m1.tiny instance during cloud-init the following pip install can experience OOM kill
         # setup swap to prevent that
         sudo dd if=/dev/zero of=/swap bs=1M count=512
         sudo chmod 600 /swap
         sudo mkswap /swap
         sudo swapon /swap
-        sudo pip install -r requirements.txt
+        sudo pip3 install -r requirements.txt
         sudo python3 setup.py install
 
         sudo sed -i -e "s#transport_url = .*#transport_url = $URL_MESSAGING#" /etc/faafo/faafo.conf