Add book that fetches program-mode function definitions from throughout the strings library, without depending on their books being certified first

git-svn-id: http://acl2-books.googlecode.com/svn/trunk@2488 303c5b2c-9740-0410-b014-fd8f9db7be32
Various updates (with Sol):

STD:
  - Somewhat refactor std/util/define to make it easier to extend
  - Add new std/util/defines book, for define-like mutual-recursions
     (somewhat preliminary)

XDOC:
  - Improve @(def ...) handling of mutual-recursion events
  - Move various xdoc testing code into xdoc/tests, and tweak
    "make xdoc" to not rebuild the tests, to make it faster.  (The
    tests are still built as part of "make all", etc.)

git-svn-id: http://acl2-books.googlecode.com/svn/trunk@2489 303c5b2c-9740-0410-b014-fd8f9db7be32
Add missing files

git-svn-id: http://acl2-books.googlecode.com/svn/trunk@2490 303c5b2c-9740-0410-b014-fd8f9db7be32
Minor package tweaks in make_cert_help.pl (fixes issue 131)

git-svn-id: http://acl2-books.googlecode.com/svn/trunk@2491 303c5b2c-9740-0410-b014-fd8f9db7be32
Reduce dependencies/speed up certification of some std/util and xdocbooks.

Mostly this just substitutes inclusion of std/strings/defs-program for
std/strings/cat and/or std/strings/defs in a few places.  So if you
find this commit breaks a book, it should suffice to include one or
both of those.

git-svn-id: http://acl2-books.googlecode.com/svn/trunk@2492 303c5b2c-9740-0410-b014-fd8f9db7be32