Bump eventlet from 0.19.0 to 0.31.0

Bumps [eventlet](https://github.com/eventlet/eventlet) from 0.19.0 to 0.31.0.
- [Release notes](https://github.com/eventlet/eventlet/releases)
- [Changelog](https://github.com/eventlet/eventlet/blob/master/NEWS)
- [Commits](https://github.com/eventlet/eventlet/compare/v0.19.0...v0.31.0)

Signed-off-by: dependabot[bot] <support@github.com>

install.sh

@@ -35,14 +35,6 @@ show_menu () {
              apt-get -y update; apt-get -y upgrade;
            fi
 
-           confirmAnswer "Would you like to install wiringPI? This is required to control the GPIO"
-           if [ $? = 0 ]; then
-             git clone git://git.drogon.net/wiringPi;
-             cd wiringPi;
-             ./build; cd ..;
-             rm -rf wiringPi;
-           fi
-
            apt-get -y install python-setuptools
            easy_install pip
            apt-get -y install python-dev

requirements.txt

@@ -1,6 +1,6 @@
 Flask==0.12.4
 Flask-SocketIO==2.6.2
-eventlet==0.19.0
+eventlet==0.31.0
 greenlet==0.4.10
 python-dateutil==2.5.3
 python-engineio==0.9.2