Add source check for symbolic link
Rename gitconfig.symlink to gitconfig
Rename gitconfig.symlink.example to gitconfig.example
Rename .env to env
Move and rename osx .env to env-osx
Add source symbolic link check
Rename .zsh_theme to zsh_theme
Add source symbolic link check & remove npm plugin
Add zsh_theme for cygwin
Add gitconfig for cygwin
Add setup_env, setup_zsh_theme, & setup_link.  Add detection for OS X and Cygwin.