Updated address provider documentation for en_NG locale (#94)

Author: chrisidakwo

docs/locales/en_NG.md

@@ -3,8 +3,12 @@
 ### `Faker\Provider\en_NG\Address`
 
 ```php
-echo $faker->county(); // 'Edo'
-echo $faker->region(); // 'Katsina'
+echo $faker->city(); // 'Edo'
+echo $faker->cityName(); // 'Edo'
+echo $faker->state(); // 'Katsina'
+echo $faker->region(); // 'South-East'
+echo $faker->streetAddress(); // '92 Rev. Oladimeji Way'
+echo $faker->streetName(); // 'Chief Olasunkanmi-fasayo Street'
 ```
 
 ### `Faker\Provider\en_NG\Person`