Delete boost.

third_party/boost/README.chromium

-This contains a stripped down version of TR1::Boost version 1.36.0.  It
-contains only the files required to use tr1::tuple in Visual Studio 2005.
-All other files have been removed.  The original packing of Boost tuple used
-to create this version was taken from the googlemock project download page:
-
-  http://googlemock.googlecode.com/files/boost_tr1_tuple_1_36_0.zip
-
-This code is released under the Boost Software License - Version 1.0.  See
-boost_1_36_0/LICENSE_1_0.txt for details.
-
-Steps to reproduce stripped down package:
-  1) Download from
-     http://googlemock.googlecode.com/files/boost_tr1_tuple_1_36_0.zip
-  2) Unzip the package.  This will create the boost_1_36_0 directory.
-  3) Create a .cpp file with one line:
-       #include <tuple>
-  4) Run this file through the Visual C++ preprocessor, making sure that the
-     same compiler options (/I, /D, etc) are the same as for the the rest
-     project, and that #{BOOST_ROOT}/boost/tr1/tr1;${BOOST_ROOT} are added
-     to the include path path.  To get the preprocess output in Visual Studio,
-     select the .cpp file, go to Properties | C/C++ | Preprocessor, and set
-     "Generate Preprocessed File" to Yes.
- *5) In the preprocessed file, find all header files referenced in the
-     boost_1_36_0 subdirectory.
-  6) For each file in the boost_1_36_0 directory, if it is not referenced in
-     the list produced in step 5, delete it.
-
-The result should be 389 files, at about 2.4 megs. Adding in the
-LICENSE_1_0.txt file brings the distribution to an even 390 files.
-
-In comparison the full expansion of boost_tr1_tuple_1_36_0.zip is 1097 files
-using 9.2 megs.
-
-* For step 5, the following bash line helps generate a list of files:
-
-    cat file.i | grep "^#line" | grep boost_1_36_0 | \
-        tr -s ' ' | cut -d ' ' -f3 | tr -d \" | sort -u