Update "st2 execution tail" CLI command to just print raw output by default.
Update "st2 execution tail" CLI command to just print raw output by
default.

User can request metadata to be included (timestamp, output type) by
passing --include-metadata flag to the command.

Plexxi/st2,StackStorm/st2,Plexxi/st2,StackStorm/st2,StackStorm/st2,nzlosh/st2,Plexxi/st2,nzlosh/st2,StackStorm/st2,Plexxi/st2,nzlosh/st2,nzlosh/st2