Add indexes for elisp manual.

* doc/lispref/display.texi (Face Functions): Add an index.

* doc/lispref/variables.texi (Variable Aliases): Add an index.

* doc/lispref/functions.texi (Defining Functions): Add an index.

* doc/lispref/nonascii.texi (Coding System Basics): Add an index.

doc/lispref/ChangeLog

@@ -1,3 +1,13 @@
+2013-08-02  Xue Fuqiao  <xfq.free@gmail.com>
+
+	* display.texi (Face Functions): Add an index.
+
+	* variables.texi (Variable Aliases): Add an index.
+
+	* functions.texi (Defining Functions): Add an index.
+
+	* nonascii.texi (Coding System Basics): Add an index.
+
 2013-07-31  Xue Fuqiao  <xfq.free@gmail.com>
 
 	* nonascii.texi (Non-ASCII Characters): Update menu.

doc/lispref/display.texi

@@ -2738,6 +2738,7 @@ differently from the default face.
 @end defun
 
 @cindex face alias
+@cindex alias, for faces
 A @dfn{face alias} provides an equivalent name for a face.  You can
 define a face alias by giving the alias symbol the @code{face-alias}
 property, with a value of the target face name.  The following example

doc/lispref/functions.texi

@@ -580,6 +580,7 @@ redefinition from unintentional redefinition.
 @end defmac
 
 @cindex function aliases
+@cindex alias, for functions
 @defun defalias name definition &optional doc
 @anchor{Definition of defalias}
 This function defines the symbol @var{name} as a function, with

doc/lispref/nonascii.texi

@@ -1012,6 +1012,7 @@ The value of the @code{:mime-charset} property is also defined
 as an alias for the coding system.
 @end defun
 
+@cindex alias, for coding systems
 @defun coding-system-aliases coding-system
 This function returns the list of aliases of @var{coding-system}.
 @end defun

doc/lispref/variables.texi

@@ -1838,6 +1838,7 @@ updates this list.
 @node Variable Aliases
 @section Variable Aliases
 @cindex variable aliases
+@cindex alias, for variables
 
   It is sometimes useful to make two variables synonyms, so that both
 variables always have the same value, and changing either one also