Support retrieving status and configuration of feed triggers

[abaruni]

This PR is to add support for retrieving the status and configuration of a feed trigger

Support has been implemented in the feed providers with the following:

apache/openwhisk-package-kafka#217 <-- Merged
apache/openwhisk-package-cloudant#137 <-- Merged
apache/openwhisk-package-alarms#101 <-- Merged

[jthomas]

Code changes LGTM with the following additions...

• Update README.md with new API details, put it under this section: (https://github.com/apache/incubator-openwhisk-client-js#create--delete-feeds)

### retrieve feeds

ow.feeds.get({feedName: '...', trigger: '...'})

The following optional parameters are supported:
...

• Update integration test for the feeds method to use the retrieval call after creation before the delete?
  https://github.com/apache/incubator-openwhisk-client-js/blob/master/test/integration/feeds.test.js

[abaruni]

@jthomas yes, this is a WIP. work on the integration tests is needed.

i've already modified the readme as follows

### retrieve resource

...
ow.feeds.get({name: '...'})

i think it best to match the pattern that is here. i.e., when the UPDATE lifecycleEvent is delivered, change the

### create & delete feeds

section to be

### create & update feeds

and remove the ow.feeds.delete({feedName: '...', trigger: '...'}) snippet in order to match

### create & update rule

### create & update packages

### create & update trigger

and then change the delete resource section to look like

### delete resource

...
ow.feeds.delete({name: '...'})

[codecov-io]

Codecov Report

Merging #80 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #80      +/-   ##
==========================================
+ Coverage   99.41%   99.41%   +<.01%     
==========================================
  Files          14       14              
  Lines         339      340       +1     
==========================================
+ Hits          337      338       +1     
  Misses          2        2

Impacted Files	Coverage Δ
lib/feeds.js	100% <100%> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 537b547...20dcac4. Read the comment docs.

[abaruni]

@jthomas i've added to the integration test. mind having another look at this?

[abaruni]

@csantanapr

[jthomas]

@abaruni Code LGTM, still need the README.md changes? Your suggestions above about the doc structure make sense. 👍

[csantanapr]

LGTM