new actions / new banners / extra type check

Add two new Actions - Events and UpdateConfig

Allow for any sequence of numerics and periods in the version number that Asterisk returns (2.5 for Asterisk 13) in the welcome banner

Some extra type checking to prevent exceptions that we have seen in production message flows.

i'm curious about why would this be necessary, since events should be by default an empty array according to: https://github.com/marcelog/Nami/blob/master/src/message/response.js#L42