fix bug in install.sh that didn't do the rm before the symlink due to $HOME being double-added to the beginning of the path.

fix bug in install.sh that didn't do the rm before the symlink due to $HOME being double-added to the beginning of the path.

also, a typical case on linux systems will be that you'll want a gitconfig to be for a different user than lehresman (or in my case, rdickey), such as ec2-user or some other org-specific user, so I changed that bit too.  Feel free to reject just wanted to contribute back