Shorten the section title.

Doc/lib/libimp.tex

 \section{\module{imp} ---
-         Access the implementation of the \keyword{import} statement.}
-\declaremodule{builtin}{imp}
+         Access the \keyword{import} internals}
 
+\declaremodule{builtin}{imp}
 \modulesynopsis{Access the implementation of the \keyword{import} statement.}
 
-\index{import}
 
-This module provides an interface to the mechanisms used to implement
-the \keyword{import} statement.  It defines the following constants and
-functions:
+This\kwindex{import} module provides an interface to the mechanisms
+used to implement the \keyword{import} statement.  It defines the
+following constants and functions:
 
 
 \begin{funcdesc}{get_magic}{}