Add new Cloudant feed parameters to event

[jthomas]

Cloudant trigger feed also supports the following parameters.

• filter
• query_params
• maxTriggers

These values need to be added the feed_parameters if present in YAML file here.

Want to be able to support this YAML example...

functions:
    index:
        handler: users.main
        events:
            - cloudant:          
                max: 10000 // maxTriggers
                query: // object YAML config
                   status: new
                filter: mailbox/by_status

[jthomas]

Fixed with: cbaa98d