14.7.3/7 is missing references to variable templates

[zygoloid]

The lists of forms of explicit and partial specializations in 14.7.3/7 is missing variable templates. This is correct, due to the "etc.", but being more explicit here may be helpful to a reader unfamiliar with this rule. (Note that in C++11, we explicitly added "member enumerations of class templates" to the first list in order to comfort gentle readers that we still loved and cared for this important paragraph.)