Clean up empty "Requirements" headings

Author: Rageking8

docs/c-runtime-library/setjmp3.md

@@ -43,8 +43,6 @@ Always returns 0.
 
 Don't use this function in a C++ program. It's an intrinsic function that doesn't support C++. For more information about how to use `setjmp`, see [Using setjmp/longjmp](../cpp/using-setjmp-longjmp.md).
 
-## Requirements
-
 ## See also
 
 [Alphabetical function reference](./reference/crt-alphabetical-function-reference.md)\

docs/cppcx/operator-type-hat.md

@@ -42,8 +42,6 @@ Type^ tx2 = (Type^)(tn);
 
 .NET Framework programs project `TypeName` as <xref:System.Type>
 
-### Requirements
-
 ## See also
 
 [operator Windows::UI::Xaml::Interop::TypeName](../cppcx/operator-windows-ui-xaml-interop-typename.md)<br/>

docs/cppcx/operator-windows-ui-xaml-interop-typename.md

@@ -42,8 +42,6 @@ Type^ tx2 = (Type^)(tn);
 
 .NET Framework programs project `TypeName` as [System.Type](/dotnet/api/system.type).
 
-### Requirements
-
 ## See also
 
 [operator Windows::UI::Xaml::Interop::TypeName](../cppcx/operator-windows-ui-xaml-interop-typename.md)<br/>

docs/cppcx/platform-ibox-interface.md

@@ -26,8 +26,6 @@ The type of the boxed value.
 
 The `IBox<T>` interface is primarily used internally to represent nullable value types, as described in [Value classes and structs (C++/CX)](../cppcx/value-classes-and-structs-c-cx.md). The interface is also used to box value types that are passed to C++ methods that take parameters of type `Object^`. You can explicitly declare an input parameter as `IBox<SomeValueType>`. For an example, see [Boxing](../cppcx/boxing-c-cx.md).
 
-### Requirements
-
 ### Members
 
 The `Platform::IBox` interface inherits from the [Platform::IValueType](../cppcx/platform-ivaluetype-interface.md) interface. `IBox` has these members: