[mod] engines - add IMDB / Internet Movie Database

Merged from @Guilvareux's commit [1] and slightly modfied / see [2].

[1] https://github.com/searx/searx/pull/2980/commits/f2f90071
[2] https://github.com/searx/searx/pull/2980

searx/settings.yml

@@ -744,6 +744,12 @@ engines:
       require_api_key: false
       results: JSON
 
+  - name: imdb
+    engine: imdb
+    shortcut: imdb
+    timeout: 6.0
+    disabled: true
+
   - name: ina
     engine: ina
     shortcut: in