Clone repo to a folder of your discretion.
Create a symlink to a folder on your path (run echo $PATH in terminal to find out what folders you have in your path).
ln -s path/to/change_localhost/c-lhost.sh chost- restart your terminal
Make sure your webserver is pointing towards ~/Sites/localhost.
run chost in the folder you want to use as localhost, or pass in a path as an argument as follows:
chost client/projname/siteroot/
chost -l returns current local host.
Now there will be a symlink to the desired web root folder. And by changing that symlink, you change your localhost. No restart of your apache/equivalent server is needed. This script automates the symlinking part.