Update Documentation for v-protocol, v-pool, and v-connection-string

[DMickens]

We need to update the documentation for the v-protocol, v-pool, and v-connection-string packages as well.

While doing this we should also add a small code snippet in the main package for importing the driver. (const {Client, Pool} = require('vertica-nodejs'))

More feedback: 'examples' directory link was accidentally removed from vertica-nodejs package README and replaced by usage examples. We ought to have both, whichever comes first should mention the second so that users dont stop at one location.