Don't duplicate enum params

The new docs look like:

  OPTIONS
         --stack-status-filter (list)
            Stack status to use as a filter. Specify one or  more  stack  status
            codes  to  list  only  stacks with the specified status codes. For a
            complete list of stack status codes, see the  StackStatus  parameter
            of the  Stack data type.

         Syntax:

            "string" "string" ...

            Where valid values are:
              CREATE_IN_PROGRESS
              CREATE_FAILED
              CREATE_COMPLETE
              ROLLBACK_IN_PROGRESS
              ROLLBACK_FAILED
              ROLLBACK_COMPLETE
              DELETE_IN_PROGRESS
              DELETE_FAILED
              DELETE_COMPLETE
              UPDATE_IN_PROGRESS
              UPDATE_COMPLETE_CLEANUP_IN_PROGRESS
              UPDATE_COMPLETE
              UPDATE_ROLLBACK_IN_PROGRESS
              UPDATE_ROLLBACK_FAILED
              UPDATE_ROLLBACK_COMPLETE_CLEANUP_IN_PROGRESS
              UPDATE_ROLLBACK_COMPLETE

Fixes #609.
Don't print tracebacks if completer is interrupted

Fixes #628.
Merge branch 'sigint-completer' into develop

* sigint-completer:
  Don't print tracebacks if completer is interrupted
Merge branch 'enum-doc-fix' into develop

* enum-doc-fix:
  Don't duplicate enum params
Update changelog with latest fixes
Update route53 test with latest model
Update changelog with latest changes
Bumping version to 1.2.13
Merge branch 'release-1.2.13' into develop

* release-1.2.13:
  Bumping version to 1.2.13
  Update changelog with latest changes
  Update route53 test with latest model
Missing --recursive option in recursive example for aws s3 ls
Remove header from ls output

We don't output those headers anymore.
Merge branch 'alanmquach-develop' into develop

* alanmquach-develop:
  Remove header from ls output
  Missing --recursive option in recursive example for aws s3 ls
Cleanup unused imports in test module
Show better error message for invalid JSON

Especially for list params, their error messages were not helpful.
Error messages now include the actual value itself, as we have seen
cases where customers specify valid JSON but the shell they're using
will process arguments and strip out characters such as quotes.
By showing the actual JSON contents it will make this more obvious.

Before:

  The value for parameter "--" must be JSON or path to file.

After:

  Error parsing parameter --block-device-mappings: Invalid JSON:
  [{ ...BAD JSON CONTENTS ...}]
Handle file:// values containing leading/trailing spaces

Fixes #631.  The issue was that shorthand processing was triggered
because we were looking at leading spaces instead of the first non
space character.
Merge branch 'json-spaces' into develop

* json-spaces:
  Handle file:// values containing leading/trailing spaces
Update changelog with issue 640
Update changelog with #637
Merge branch 'multi-json-arg' into develop

* multi-json-arg:
  Show better error message for invalid JSON
  Cleanup unused imports in test module
Add changelog entry for #639