Fix paths so rspec can run in vim

Mac OS X

If you have administrator privileges, you must fix an Apple-introduced problem in Mac OS X 10.5 Leopard by executing the following command, or BASH and Zsh will have the wrong PATH when executed non-interactively.

sudo chmod ugo-x /usr/libexec/path_helper
path_helper is intended to make it easier for installers to add new paths to the environment without having to edit shell configuration files by adding a file with a path to the /etc/paths.d directory.

Unfortunately, path_helper always reads paths from /etc/paths set by Apple then paths from /etc/paths.d set by third party installers, and lastly paths from the PATH environment variable set by the parent process, which ultimately is set by the user with export PATH=... Thus, it reorders path priorities, and user /bin directories meant to override system /bin directories end up at the tail of the array.

https://github.com/dotphiles/dotzsh#mac-os-x