Allow users to send any log-driver to Docker/ECS
Allow users to send any log-driver to Docker/ECS

This removes any contraints on what log-drivers are possible from Empire, simply relying on ECS and
Docker to handle errors in the case that an invalid log-driver is sent in.

Closes #925

remind101/empire,mhahn/empire,remind101/empire,iserko/empire,remind101/empire,iserko/empire,mhahn/empire,mhahn/empire,iserko/empire