Patch for boost-1_54_0 to build with clang++ on Xcode.

gistfile1.txt

diff -ur boost_1_54_0-PRISTINE/tools/build/v2/user-config.jam boost_1_54_0/tools/build/v2/user-config.jam
--- boost_1_54_0-PRISTINE/tools/build/v2/user-config.jam        2011-01-25 12:06:12.000000000 -0600
+++ boost_1_54_0/tools/build/v2/user-config.jam 2013-10-18 10:57:15.000000000 -0500
@@ -90,3 +90,10 @@
 
 # Configure specific Python version.
 # using python : 3.1 : /usr/bin/python3 : /usr/include/python3.1 : /usr/lib ;
+#
+
+# ---------------------
+# Clang configuration.
+# ---------------------
+
+using clang : : /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ ;