move image name into correct position

Docker-DCO-1.1-Signed-off-by: Aaron Feng <aaron.feng@gmail.com> (github: aaronfeng)
Use exec to replace bash with apache2 after environment is set up
Docker-DCO-1.1-Signed-off-by: Mike Naberezny <mike@naberezny.com> (github: mnaberez)
Merge pull request #3770 from aaronfeng/fix-image-name-pos

move image name into correct position
Merge pull request #3773 from mnaberez/supervisord-apache2-example

Use exec to replace bash with apache2 after environment is set up