Giving either --install or --update flag is neccessary for the script to proceed
-i | --install => Install the config.
-u | --update => Update the existing config without removing existing stuff.
-b | --backup 'path' => Custom config backup path.
-nb | --no-backup => Don't take existing config backup. Use with caution.
Update formatting using following command
shfmt -i 2 -sr -p -bn -ci -w install.sh
* modify sed command to work in both gnu sed and mac os sed
https://stackoverflow.com/a/4247319
* use printf everywhere for more compatibility
* add some error checking
Akianonymus