Raspberry Pi 2 - Raspbian - Configuration for enabling SSH over Wifi (without the need for the ethernet cable)

interfaces

#Filename: /etc/network/interfaces

# interfaces(5) file used by ifup(8) and ifdown(8)

# Please note that this file is written to be used with dhcpcd
# For static IP, consult /etc/dhcpcd.conf and 'man dhcpcd.conf'

# Include files from /etc/network/interfaces.d:
source-directory /etc/network/interfaces.d

allow-hotplug eth0
iface eth0 inet loopback
iface eth0 inet static
        address 192.168.1.70
        netmask 255.255.255.0
        gateway 192.168.1.254

allow-hotplug wlan0
iface wlan0 inet static
   address 192.168.1.80
   netmask 255.255.255.0
   wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
   post-up /var/helpers/wifi.sh

wifi.sh

#!/bin/bash

#Filename: /var/helpers/wifi.sh

#wait a little bitch!
sleep 30

#change the metric (priority) of the route (for the wlan0 interface) - outgoing
sudo route add -net default gw 192.168.1.254 netmask 0.0.0.0 dev wlan0 metric 0
sudo route del -net default gw 192.168.1.254 netmask 0.0.0.0 dev wlan0 metric 303

#change the metric (priority) of the route (for the wlan0 interface) - outgoing
sudo route del -net default gw 192.168.1.254 netmask 0.0.0.0 dev eth0 metric 0
sudo route add -net default gw 192.168.1.254 netmask 0.0.0.0 dev eth0 metric 2

#change the metric (priority) of the route (for the wlan0 interface) - incoming
sudo route del -net 192.168.1.0 gw 0.0.0.0 netmask 255.255.255.0 dev eth0 metric 202
sudo route del -net 192.168.1.0 gw 0.0.0.0 netmask 255.255.255.0 dev eth0 metric 0
sudo route add -net 192.168.1.0 netmask 255.255.255.0 dev eth0 metric 400