Add set, and histogram reporting to aerospike telegraf plugin

[grossjo]

refactored to allow non integration tests
fix tests to work with aerospike 4.9.0.11

Required for all PRs:

• Signed CLA.
• Associated README.md updated.
• Has appropriate unit tests.

[ssoroka]

Thanks!

Looks like github.com/influxdata/telegraf/plugins/inputs/net_response failed, but only on darwin. Going to rerun it to see if it was just an intermittent fluke.

Will review

[grossjo]

I attempted to make it backwards compatible, where all new features are opt-in.
Which should be good for any existing users of this plugin.

[grossjo]

Hi,
Just wondering what it would take to get this merged in?

[ssoroka]

Looks good. I have 2 comments you can optional address. I'll merge when you're ready.

[ssoroka]

You inherited this, but there's an opportunity to clean it up. plugins can have an Init() function that allows you to do init and config related things that runs once and before the first Gather call.

Just add func (a *Aerospike) Init() error { and you can move all this setup-related stuff there.

[grossjo]

maybe next time we do more work, we'll update this. Did not have time this iteration

[grossjo]

I'll add the init function, Didn't know about that.
Give me a day.

[grossjo]

All changes we are going to do this time are pushed up. If you are good with this PR, feel free to merge.

[ssoroka]

Thanks, Josh :)