Feature: bang & external bang can be written in upper case

Close #1223

searx/query.py

@@ -153,7 +153,7 @@ class ExternalBangParser(QueryPartParser):
         return raw_value.startswith('!!')
 
     def __call__(self, raw_value):
-        value = raw_value[2:]
+        value = raw_value[2:].lower()
         found, bang_ac_list = self._parse(value) if len(value) > 0 else (False, [])
         if self.enable_autocomplete:
             self._autocomplete(bang_ac_list)
@@ -180,7 +180,7 @@ class BangParser(QueryPartParser):
         return raw_value[0] == '!'
 
     def __call__(self, raw_value):
-        value = raw_value[1:].replace('-', ' ').replace('_', ' ')
+        value = raw_value[1:].replace('-', ' ').replace('_', ' ').lower()
         found = self._parse(value) if len(value) > 0 else False
         if found and raw_value[0] == '!':
             self.raw_text_query.specific = True
@@ -221,7 +221,7 @@ class BangParser(QueryPartParser):
 
         # check if query starts with category name
         for category in categories:
-            if category.startswith(value):
+            if category.lower().startswith(value):
                 self._add_autocomplete(first_char + category.replace(' ', '_'))
 
         # check if query starts with engine name
@@ -231,7 +231,7 @@ class BangParser(QueryPartParser):
 
         # check if query starts with engine shortcut
         for engine_shortcut in engine_shortcuts:
-            if engine_shortcut.startswith(value):
+            if engine_shortcut.lower().startswith(value):
                 self._add_autocomplete(first_char + engine_shortcut)