Fix IMDDOS example

[clenk]

The IMDDOS Botnet Report example on the examples page links to a gist. We should move it into this repo and fix/update the content (It's a STIX 2.0 bundle, but it contains a Location object).

[srrelitz2]

@clenk @ejratl -- Is this issue still relevant or applicable for where we are now with STIX 2.1 and beyond?

[ejratl]

Yes, this example does need to be updated as @clenk describes. You can see it here: https://oasis-open.github.io/cti-documentation/stix/examples It is the last example on the page and it links to a gist, rather than STIX content hosted on the documentation site. It would be nice if this were a 2.1 bundle rather than a 2.0 bundle.