- More code cleanup and codestyle updates

- Fixed some possible nullref exceptions
- Methods signatures now have up to 3 parameters before breakaing down each parameter in a separate line
- Method invocations have the same rule, except the first parameter will be in the same line as the invocation to prevent some ugliness when passing lambas as arguments
- Applied many more codestyles
- Extensions folder fully reformatted

src/NadekoBot/Modules/Searches/XkcdCommands.cs

@@ -11,9 +11,7 @@ public partial class Searches
         private readonly IHttpClientFactory _httpFactory;
 
         public XkcdCommands(IHttpClientFactory factory)
-        {
-            _httpFactory = factory;
-        }
+            => _httpFactory = factory;
 
         [NadekoCommand, Aliases]
         [Priority(0)]