[time.point.cast] replaces braces with parentheses

Fixes #562.

Author: jwakely

source/utilities.tex

@@ -12376,7 +12376,7 @@
 unless \tcode{ToDuration} is a specialization of \tcode{duration}.
 
 \pnum
-\returns \tcode{time_point<Clock, ToDuration>{floor<ToDuration>(tp.time_since_epoch())}}.
+\returns \tcode{time_point<Clock, ToDuration>(floor<ToDuration>(tp.time_since_epoch()))}.
 \end{itemdescr}
 
 \indexlibrary{\idxcode{time_point}!\idxcode{ceil}}%
@@ -12393,7 +12393,7 @@
 unless \tcode{ToDuration} is a specialization of \tcode{duration}.
 
 \pnum
-\returns \tcode{time_point<Clock, ToDuration>{ceil<ToDuration>(tp.time_since_epoch())}}.
+\returns \tcode{time_point<Clock, ToDuration>(ceil<ToDuration>(tp.time_since_epoch()))}.
 \end{itemdescr}
 
 \indexlibrary{\idxcode{time_point}!\idxcode{round}}%
@@ -12411,7 +12411,7 @@
 \tcode{treat_as_floating_point<typename ToDuration::rep>::value} is \tcode{false}.
 
 \pnum
-\returns \tcode{time_point<Clock, ToDuration>{round<ToDuration>(tp.time_since_epoch())}}.
+\returns \tcode{time_point<Clock, ToDuration>(round<ToDuration>(tp.time_since_epoch()))}.
 \end{itemdescr}
 
 \rSec2[time.clock]{Clocks}