Add paths for Homebrew's gcc and g++

Compile.rst

@@ -123,12 +123,22 @@ If you are building on 10.6, please read the subsection below titled "Snow Leopa
     git submodule init
     git submodule update
 
-7. Build dfhack::
+7. Set environment variables:
+
+  Macports::
 
-    mkdir build-osx
-    cd build-osx
     export CC=/opt/local/bin/gcc-mp-4.5
     export CXX=/opt/local/bin/g++-mp-4.5
+
+  Homebrew::
+
+    export CC=/usr/local/bin/gcc-4.5
+    export CXX=/usr/local/bin/g++-4.5
+
+8. Build dfhack::
+
+    mkdir build-osx
+    cd build-osx
     cmake .. -DCMAKE_BUILD_TYPE:string=Release -DCMAKE_INSTALL_PREFIX=/path/to/DF/directory
     make
     make install