Proposal: MultiBot sample

[carlosscastro]

Proposal: create a sample showing multi-bot support where a single bot service endpoint hosts several bots. Many customers reach out for this functionality.

Attached file EchoBot_MultiCredentialProvider.zip
is a minimal V3 sample for C#. The work would be to port it to V4 languages. (Thanks @EricDahlvang)

Arguably, this could also be captured in a blog post if we deem it not important enough to deserve a sample.

[benbrown]

Using the MVC approach, doing a multi-bot app is much easier than it used to be. We're not planning to create a sample dedicated specifically to this, but a blog post is a good idea!