Run examples in the continuous integration

[yupinghu]

After we have mocks for request/response (and eventually for everything), we should hook up running the examples during CI, to detect when there are errors in the examples. (See #81, for example.)

[ericlu88]

The mock layer is substituting the blpapi-wrapper and have no knowledge of implementation details of it, so it won't be able to catch the service name error in #81, at least for now. We have to think it more if we want to capture that.

[thmiceli]

How is a mock layer of blpapi-wrapper useful?
Would it be possible to have a mock layer that is a replacement of blpapi-node instead? This would facilitate deterministic regression testing of the blpapi-wrapper.

[ericlu88]

The idea is to push blpapi-wrapper down to blpapi-node project, so that blpapi-http project is purely http server related functionality, which is the focus of our testing.

[yupinghu]

Ah ok. I was thinking that we'd actually run much of the real blpapi-wrapper code and therefore the errors generated by the request name map checks would fire. I would probably advocate for this regardless of what lives where, i.e. have the mock be a replacement for blpapi-wrapper as you suggest but share as much of the code as possible and only fake the calls to the underlying API as much as possible.