examples/var_service/supplicant_if: new service example

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

examples/var_service/supplicant_if/wpa_supplicant.conf

@@ -0,0 +1,28 @@
+# allow frontend (e.g., wpa_cli) to be used by all users in 'wheel' group
+ctrl_interface=DIR=/var/run/wpa_supplicant
+#GROUP=wheel
+
+# Typical minimal wifi setup:
+network={
+    ssid="--your-ESSID--"
+    key_mgmt=WPA-PSK
+    psk="--your-password--"
+}
+
+# Other fields:
+#    scan_ssid=1
+#    key_mgmt=WPA-EAP WPA-PSK IEEE8021X NONE
+#    pairwise=CCMP TKIP
+#    group=CCMP TKIP WEP104 WEP40
+#    psk="very secret passphrase"
+#    eap=TTLS PEAP TLS
+#    identity="user@example.com"
+#    ca_cert="/etc/cert/ca.pem"
+#    client_cert="/etc/cert/user.pem"
+#    private_key="/etc/cert/user.prv"
+#    private_key_passwd="password"
+#    phase1="peaplabel=0"
+#    ca_cert2="/etc/cert/ca2.pem"
+#    client_cert2="/etc/cer/user.pem"
+#    private_key2="/etc/cer/user.prv"
+#    private_key2_passwd="password"