Duplicate elasticache.NodeGroupConfiguration definition causing type check failure

[jjpestacio]

There are two class definitions for NodeGroupConfiguration:
https://github.com/cloudtools/troposphere/blob/master/troposphere/elasticache.py#L101
https://github.com/cloudtools/troposphere/blob/master/troposphere/elasticache.py#L162

This causes a type check failure when creating a ReplicationGroup with a NodeGroupConfiguration:

TypeError: <class 'troposphere.elasticache.ReplicationGroup'>: replicationgroupredisclustertest2.NodeGroupConfiguration is <class 'troposphere.elasticache.NodeGroupConfiguration'>, expected [<class 'troposphere.elasticache.NodeGroupConfiguration'>]

When importing NodeGroupConfiguration, the latter class is used but during validation for ReplicationGroup the former class is used.

The resolution is to remove one of the NodeGroupConfiguration class definitions. Note that there is a difference between the types of NodeGroupId in the class definitions.

[markpeek]

Thank you @jjpestacio. Just pushed a fix if you want to test it.