Update Travel Sample Application for Couchbase 4.5 Features

Update the travel sample application to cover 4.5 features such as FTS and resolve inconsistencies where encountered.

There is a draft of a REST API spec for a v2 of the backend. It describes a controller that demonstrates use of FTS and Subdoc.

The frontend has been rewritten in Angular2 addressing inconsistencies in the backend. The Java wip frontend lives in couchbaselabs/try-cb-frontend. The goal is for this to be a 100% common frontend across all backends.

Work toward this v2 should be made in its own branch, and the embedded angular1 app should be ignored and ultimately replaced by the one produced by `try-cb-frontend` when its done.

Currently the Java backend that conforms to the v2 specification is in the `api/v2` branch.

(description borrowed from Simon Baslé's writeup)