Added script for building Boost with GCC

lib/build-gcc.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+# This build script is for OS X Lion users who have compiled openmpi and
+# clang-3.1 from MacPorts.  I build my own Boost instead of using MacPorts'
+# Boost in order to get better debugging support, and to link with libc++.
+
+export PATH=$PATH:/opt/local/lib/openmpi/bin
+
+cat > ~/user-config.jam <<EOF
+using clang-darwin : : "/usr/local/bin/clang++" : <cxxflags>-std=c++11 <include>/usr/local/include ;
+EOF
+
+# jww (2012-04-24): This is still linking against /usr/lib/libc++.1.dylib
+# instead of /usr/local/lib/libc++.1.dylib
+make "$@" OPTJ=-j20     \
+    BOOST_DEFINES="-sICU_PATH=/opt/local cxxflags=\"-I/opt/local/include\" linkflags=\"-L/opt/local/lib\""