Duplicate message posting fix

Updated the DynamoPackages.com version to 1.3.6 to include the fixes in 8f5fd11

Initial release

This is the first public release of DynaSlack.
Following on from the UKDynUG presentation of the DynaSlack prototype, the project underwent a few quick refactors to make the code more modular, more aligned with OOP practices and most importantly more legible. The project was also re-organised to make it more user-friendly to interact with in Dynamo.