[class.derived] has confusing cross-reference for inheriting constructors

[jwakely]

[class.derived] p2 says:

Constructors of a base class can also be inherited as described in 10.3.3.

But 10.3.3 is only about the syntax, it says nothing much about inheriting constructors. Could we also have a cross-reference to 15.6.3 [class.inhctor.init], even if only in a note?

Constructors of a base class can also be inherited as described in 10.3.3. [Note: But don't look there, you're probably trying to find 15.6.3 instead. --end note]

[jensmaurer]

@zygoloid objects; see #1687.