Js mqtt - PR #1 Preliminary Foundation

[bretambrose]

Fixes and updates to support an internal pure JS MQTT client implementation:

• Heap implementation to support operation timeout tracking
• Refactor reconnect wait calculations to be shared since the new client will be doing the same thing
• Accurate type annotations for our websocket connectors
• Fix a bug in buffered event emitter that would cause incorrect behavior if cork/uncork was used multiple times
• Add MQTT 311 reason codes to the MQTT5 reason code enums to support a client that can handle both protocols
• Add/refactor shared topic and topic filter analysis functions to support what the client will need

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.