[class.free] Change subclause heading and add indexing

Rename the heading to "Allocation and deallocation functions",
which is more appropriate for the contents of the subclause.

Author: jensmaurer

source/classes.tex

@@ -2864,11 +2864,12 @@
 \end{codeblock}
 \end{example}
 
-\rSec2[class.free]{Free store}%
+\rSec2[class.free]{Allocation and deallocation functions}%
 \indextext{free store}%
 
 \pnum
-\indextext{\idxcode{new}!type of}
+\indextext{\idxcode{new}!type of}%
+\indextext{allocation function!class-specific}%
 Any allocation function for a class
 \tcode{T}
 is a static member (even if not explicitly declared
@@ -2895,6 +2896,7 @@
 
 \pnum
 \indextext{\idxcode{delete}!type of}%
+\indextext{deallocation function!class-specific}%
 Any deallocation function for a class
 \tcode{X}
 is a static member (even if not explicitly declared