Remove global 'using_tor_proxy' and add it to the Tor engines individually

Only the engines which require Tor need to be checked

searx/settings.yml

@@ -135,7 +135,6 @@ outgoing:
   #      - http://proxy1:8080
   #      - http://proxy2:8080
   #
-  #  using_tor_proxy: true
   #
   # Extra seconds to add in order to account for the time taken by the proxy
   #
@@ -254,6 +253,7 @@ engines:
   # Requires Tor
   - name: ahmia
     engine: ahmia
+    using_tor_proxy: false
     categories: onions
     enable_http: true
     shortcut: ah
@@ -1272,6 +1272,7 @@ engines:
   # Requires Tor
   - name: torch
     engine: xpath
+    using_tor_proxy: false
     paging: true
     search_url:
       http://xmh57jrknzkhv6y3ls3ubitzfqnkrwxhopf5aygthi7d6rplyvk3noyd.onion/cgi-bin/omega/omega?P={query}&DEFAULTOP=and