[memory] Create new clause

and move [memory], [smartptr], [mem.res], and [allocator.adaptor]
from [utilities] into the new clause.

Author: jensmaurer

source/lib-intro.tex

@@ -29,6 +29,7 @@
 \ref{support}           & Language support library    \\
 \ref{concepts}          & Concepts library            \\
 \ref{diagnostics}       & Diagnostics library         \\
+\ref{mem}               & Memory management library   \\
 \ref{utilities}         & General utilities library   \\
 \ref{strings}           & Strings library             \\
 \ref{containers}        & Containers library          \\
@@ -59,6 +60,10 @@
 The diagnostics library\iref{diagnostics} provides a consistent framework for
 reporting errors in a \Cpp{} program, including predefined exception classes.
 
+\pnum
+The memory management library\iref{mem} provides components for
+memory management, including smart pointers and scoped allocators.
+
 \pnum
 The general utilities library\iref{utilities} includes components used
 by other library elements, such as a predefined storage allocator for dynamic