Add id field to chapter and book tags to allow output file names

 to be meaningful.

doc/src/sgml/admin.sgml

@@ -18,7 +18,7 @@
 <!entity biblio   SYSTEM "biblio.sgml">
 ]>
 <!-- entity manpages SYSTEM "man/manpages.sgml" subdoc -->
-<Book>
+<Book Id="admin">
 
 <!-- Title information -->
 

doc/src/sgml/advanced.sgml

-<Chapter>
+<Chapter Id="advanced">
 <Title>Advanced <ProductName>Postgres</ProductName> <Acronym>SQL</Acronym> Features</Title>
 
 <Para>

doc/src/sgml/array.sgml

-<Chapter>
+<Chapter Id="arrays">
 <Title>Arrays</Title>
 
 <Para>

doc/src/sgml/compiler.sgml

-<Chapter>
+<Chapter Id="compiler">
 <DocInfo>
 <AuthorGroup>
 <Author>

doc/src/sgml/datatype.sgml

-<Chapter>
+<Chapter Id="datatype">
 <Title>Data Types</Title>
 
 <Abstract>

doc/src/sgml/dfunc.sgml

-<Chapter>
+<Chapter Id="dfunc">
 <Title>Linking Dynamically-Loaded Functions</Title>
 
 <Para>

doc/src/sgml/ecpg.sgml

-<Chapter>
+<Chapter Id="ecpg">
 <DocInfo>
 <AuthorGroup>
 <Author>

doc/src/sgml/environ.sgml

-<Chapter>
+<Chapter Id="environ">
 <Title>Setting Up Your Environment</Title>
 
 <Para>

doc/src/sgml/extend.sgml

-<Chapter>
+<Chapter Id="extend">
 <Title>Extending <Acronym>SQL</Acronym>: An Overview</Title>
 
 <Para>

doc/src/sgml/func-ref.sgml

-<Chapter>
+<Chapter Id="func-ref">
 <Title>Functions</Title>
 
 <Abstract>

doc/src/sgml/gist.sgml

-<Chapter>
+<Chapter Id="gist">
 <DocInfo>
 <AuthorGroup>
 <Author>

doc/src/sgml/inherit.sgml

-<Chapter>
+<Chapter Id="inherit">
 <Title>Inheritance</Title>
 
 <Para>

doc/src/sgml/install.sgml

-<Chapter>
+<Chapter Id="install">
 <Title>Installation</Title>
 
 <Abstract>

doc/src/sgml/jdbc.sgml

-<Chapter>
+<Chapter Id="jdbc">
 <Title>JDBC Interface</Title>
 
 <Para>

doc/src/sgml/libpq.sgml

-<Chapter>
+<Chapter Id="libpq">
 <Title><FileName>libpq</FileName></Title>
 
 <Para>

doc/src/sgml/lobj.sgml

-<Chapter>
+<Chapter Id="largeObjects">
 <Title>Large Objects</Title>
 
 <Para>

doc/src/sgml/manage.sgml

-<Chapter>
+<Chapter Id="manage">
 <Title>Managing a Database</Title>
 
 <Para>

doc/src/sgml/odbc.sgml

-<Chapter>
+<Chapter Id="odbc">
 <DocInfo>
 <AuthorGroup>
 <Author>

doc/src/sgml/pgaccess.sgml

-<Chapter>
+<Chapter Id="pgaccess">
 <Title><Command>pgaccess</Command></Title>
 
 <Para>

doc/src/sgml/programmer.sgml

@@ -59,7 +59,7 @@
 <!entity contacts SYSTEM "contacts.sgml">
 ]>
 <!-- entity manpages SYSTEM "man/manpages.sgml" subdoc -->
-<Book>
+<Book Id="programmer">
 
 <!-- Title information -->