Remove internals2 book

Cf. <php/doc-en#152>.

Author: cmb69

manual.xml.in

@@ -436,26 +436,6 @@
   </set>
  </set>
 
- <book xml:id="internals2">
-  <title>&Internals2;</title>
-  &internals2.intro;
-  &internals2.memory.index;
-  &internals2.variables.index;
-  &internals2.funcs.index;
-  &internals2.objects.index;
-  &internals2.resources.index;
-  &internals2.ini.index;
-  &internals2.streams.index;
-  &internals2.counter;
-  &internals2.buildsys.index;
-  &internals2.structure.index;
-  &internals2.pdo.index;
-  &internals2.faq.index;
-  &internals2.apiref.index;
-  &internals2.opcodes;
-  &internals2.ze1.index;
- </book>
-
  <book xml:id="faq">
   <title>&FAQ;</title>
   <titleabbrev>&FAQabbrev;</titleabbrev>