Error out sooner

[zgulde]

We should probably bail out of the site create command after we fail to create the user and the group

 rpal@Rons-MBP blog % codeup_blog site create --domain ronnelpalencia.com --java --spring-boot --port 8080
- Making Sure ronnelpalencia.com Isn't Already Setup...
  ok
- Checking To Make Sure Port 8080 Is Free...
  ok
- Checking DNS Records For ronnelpalencia.com...
  ok
- Logging In To Create ronnelpalencia.com...
- Creating User and Group For ronnelpalencia.com
useradd: group ronnelpalencia-com exists - if you want to add this user to that group, use -g.
Connection to 68.183.114.117 closed.
- Performing Extra Spring Boot Configuration
Performing spring boot app configuration...
sed: can't read /srv/ronnelpalencia.com/config: No such file or directory
- Finished Setting Up ronnelpalencia.com
rpal@Rons-MBP blog %

Also it seems like there's a bug here somewhere in creating/removing the user+group for a site