Extend dependency commands to support the same project existing in more than one Org

[carwin]

Extrapolated from #5, this is a bit of an edge case but not out of the realm of possibility. At the moment the dependency commands take a project name, and use that to find the the parent org ID necessary for the API call -- what would happen if a user tracked the same project in two Orgs?

To handle that, we should allow users to specify their org ID in the command - though this will need to be balanced with other potential additions to the dependency command(s) and their order in the syntax.

The original thought is something like:

    /snyk dependencies <Project Name> <Org Name>
    /snyk dependencies <Project ID> <Org Name>
    /snyk dependencies <Project Name> <Org ID>
    /snyk dependencies <Project ID> <Org ID>