Add Typescript types

[asselin]

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What

Added typescript definition files.

How

Adde Typescript definition files for the JS API to the types/ folder, and converted samples to TS.

Testing

The sample files should compile and run.

Issues

https://github.com/ibm-messaging/mq-mqi-nodejs/issues/132

[sticzaIDBC]

Would be great to have this one merged :rocket:

[ibmmqmet]

Once again, thanks for the work on this. It's now been merged and published as part of 0.9.20