Adding licenses to some files I wrote over the summer.

fixes issue 129

Note: I'm submitting this from my personal laptop, which is very slow.  I don't want to wait 4 hours to rebuild the books, so while I doubt this commit breaks the books, you might not want to update ths directory to this revision until I send an 'all clear' notice.

git-svn-id: http://acl2-books.googlecode.com/svn/trunk@2506 303c5b2c-9740-0410-b014-fd8f9db7be32
Mostly VL updates, inching toward SystemVerilog support
 - Clean up existing preprocessor code using define
 - Get rid of lexconfigs (use loadconfigs instead)
 - Move preprocessor and parser into their own subdirectories
 - Rework some uses of nreverse using nrev

NREV: new books, see centaur/nrev
 - This gives you something like the memory efficiencies of nreverse.  It's not
   quite as fast as using nreverse directly, but the overhead seems pretty
   reasonable.

STD updates:
 - Minor changes to reduce dependencies in various std/util files, e.g.,
   no longer depending on misc/assert or misc/definline
 - Initial work towards using define throughout the std/strings library,
   mainly to improve documentation

git-svn-id: http://acl2-books.googlecode.com/svn/trunk@2507 303c5b2c-9740-0410-b014-fd8f9db7be32