Changed Propertiest to Map for custom WebSocket Headers (502)

[vit21ik]

Signed-off-by: Vitalii vitalii.vlasiuk@temy.co

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Changed Properties to Map for Custom WebSocket Headers

[davidgraeff]

@jpwsutton Can this change be implemented? The old properties interface really makes no sense here and in Eclipse Smarthome the given Maps would require an unnecessary conversion.