Rename some entities so they don't clash with hslibs.
<Chapter id="ghc-language-features">
<Title>GHC Language Features</Title>
<Chapter id="ghc-language-features">
<Title>GHC Language Features</Title>
<!ENTITY prof SYSTEM "profiling.sgml" >
<!ENTITY debug SYSTEM "debugging.sgml" >
<!ENTITY sooner SYSTEM "sooner.sgml" >
<!ENTITY prof SYSTEM "profiling.sgml" >
<!ENTITY debug SYSTEM "debugging.sgml" >
<!ENTITY sooner SYSTEM "sooner.sgml" >
-<!ENTITY lang SYSTEM "lang.sgml" >
-<!ENTITY glaexts SYSTEM "glasgow_exts.sgml" >
+<!ENTITY lang-features SYSTEM "lang.sgml" >
+<!ENTITY glasgowexts SYSTEM "glasgow_exts.sgml" >
<!ENTITY parallel SYSTEM "parallel.sgml" >
<!ENTITY vs-hs SYSTEM "vs_haskell.sgml" >
<!ENTITY wrong SYSTEM "gone_wrong.sgml" >
<!ENTITY parallel SYSTEM "parallel.sgml" >
<!ENTITY vs-hs SYSTEM "vs_haskell.sgml" >
<!ENTITY wrong SYSTEM "gone_wrong.sgml" >