Library clauses misuse "an instance of"

[jwakely]

We usually use "an instance of" to mean "an object of type", but the following use it to mean "a specialization of" and should probably be changed:

• [func.wrap.func.con] p9
• [time.point] p2
• [time.hms.overview] p2
• [fpos.operations] p1
• [streambuf.virt.put] footnote 299