"TASK_DEFINITION_ARN: unbound variable" when using with task definition "-d" option

[bfolkens]

When using the -d or --task-definition option, an error is produced:

/ecs-deploy: line 464: TASK_DEFINITION_ARN: unbound variable

It seems as though the TASK_DEFINITION_ARN is not getting set since SERVICE is false (as it should be), though that branch of code is what is responsible for setting TASK_DEFINITION_ARN.

[mnc]

I'm facing the same error like below log.

/usr/local/bin/ecs-deploy: line 567: TASK_DEFINITION_ARN: unbound variable

Could you merge this PR?
I'll try to fix it if there is any problem.

[thomasbiddle]

Also hitting this issue; looks like I'll just have to patch my own copy

[fillup]

@thomasbiddle #99 also includes some new functionality so I can't just merge in the fix for the unbound variable. If you want to put it in as a new PR I'll be happy to review and merge it in.