Failures are not honoring retry index

[davegraham92120]

There is an unused deprecated script flush queue () #dep, which appears to increment the message queue retryIndex, however the new version of this script flush queue does not. Unless there's a hard failure (i.e., error code 104) the message will be tried for eternity.

[davegraham92120]

After further review, it appears that the field MESSAGEQUEUE::retryIndex is being conflated with and looking up from the field SUBSCRIBER::retryLimit. The index should be the current retry count and it should halt once it reaches the limit.

Also, the field SUBSCRIBER::retryLimit needs to be added to the Subscribers layout so a user can edit this value.