Eliminate unused and undocumented block
Downcase revised host on middleware init instead of each call
Enable mapping multiple legacy hosts to a single new host via array key in mapping
Leverage stdlib URI instead of custom regex for url modification
Enable setting additional URI properties via setting new host to a hash of URI-acceptable key values
Raise ArgumentError if host key is not specified
Detect circular redirects at initialization time
No need to check for URI setter existence. Bad values should raise exceptions
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Version 1.2