SCons not installing in Mavericks

SCons appears to not be linking to the right executable directory when building on Mavericks:

```
└$ brew install scons
==> Downloading http://downloads.sourceforge.net/scons/scons-2.3.0.tar.gz
######################################################################## 100.0%
==> /usr/local/opt/python/bin/python2 setup.py install --prefix=/usr/local/Cellar/scons/2.3.0 --standa
 /usr/local/Cellar/scons/2.3.0: 7 files, 328K, built in 3 seconds


└$ scons
zsh: command not found: scons
```

This adds the script to the correct path.

This issue also breaks the install of MongoDB. See #23702 and my last comment for a workaround.