feat: Deleting environments with globally deployed Aurora DB and improvements to EC2RouteTable, ElasticacheReplicationGroup and ElasticacheSubnetGroup properties

[rotarat]

This PR covers the code needed for successful deletion of environments with a global Aurora DB and a secondary cluster in another region.
I have also added specific properties to EC2RouteTable, ElasticacheReplicationGroup and ElasticacheSubnetGroup.

[ekristen]

Due to the age and the size of this PR and the complexity and since the fork has diverged significantly I unfortunately am going to have to close this PR with merging.

If you can open an issue on the fork and describe the problem you are trying to solve or would like to open a PR on the fork please do.

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Please see the copy of the notice from the README about the deprecation of this project. Sven was kind enough to grant me access to help triage and close issues and pull requests that have already been addressed in the actively maintained fork. Some additional information is located in the welcome issue for more information.

Caution

This repository for aws-nuke is no longer being actively maintained. We recommend users to switch to the actively maintained fork of this project at ekristen/aws-nuke.
We appreciate all the support and contributions we've received throughout the life of this project. We believe that the fork will continue to provide the functionality and support that you have come to expect from aws-nuke.
Please note that this deprecation means we will not be addressing issues, accepting pull requests, or making future releases from this repository.
Thank you for your understanding and support.