Memory Leak - new Cluster under Configure may create multiple instances without using them

[roikatz]

Under the MultiCluster there is a Configure method.
This method is responsible for configuring a new cluster instance and authenticate.

under ideal conditions, this method would be called once, however, it might not be the case.

https://github.com/couchbaselabs/couchbase-aspnet/blob/3.0/src/Couchbase.AspNet/MultiCluster.cs#L63

the line #63 -> var cluster = new Cluster(clientConfig);
is being called anyway and later on, if it exists in the dictionary (AddCluster(cluster, name)) - it wouldn't be added, however, it's resources aren't cleaned immediately, which can cause memory leaks.

Suggestion for a fix so a new cluster wouldn't be created each time it accessed:
var section = (ICouchbaseClientDefinition)ConfigurationManager.GetSection(name);
var clientConfig = new ClientConfiguration(section) {Transcoder = () => new BinaryTranscoder()};
if (!Clusters.TryGet(name))
var cluster = new Cluster(clientConfig);