[Refactor] Add a default http handler to Skill

[harrisonhjones]

Notes

• Type: feature
• Issue: #22

To make life easier for skill developers I have added a default HTTP handler to the customskill package in this code change. See the example in customskill/examples/http.go. Tests have 100% coverage.

[harrisonhjones]

Friendly ping to @mikeflynn to take a look at this. I did this in response to your "let's make things easier for skill developers" comment on my last PR.

[mikeflynn]

This helps, but we should probably make the example do something, even if it just returns a voice response of "Hello world from go-alexa" would be something so a developer can see how to fully use the library.

[rking788]

I think that makes sense too. I wonder if there should be a way to add links to existing skills that use this package? or repositories on Github that use it? That way it would be a way to show more examples of how to use the package as well as the other directives (and also good advertisement for anyone with a deployed skill).

[harrisonhjones]

Yea, I'm down for adding an example. I'm working on something unlated to an Alexa skill at the moment but once I get back into Alexa development, maybe tonight if things go well, I'll look at addressing these conflicts and add examples.