logging: change resource argument to metadata

[stephenplusplus]

Fixes #1348

Before

var resource = {
  type: 'gce_instance',
  labels: {
    zone: 'global',
    instance_id: '3'
  }
}

var entry = log.entry(resource, data)
entry.otherMetadataProperty = '...' // <- not documented this way, because it wasn't intended to be done this way

After

var metadata = {
  otherMetadataProperty: '...', // <- logical place for this
  resource: {
    type: 'gce_instance',
    labels: {
      zone: 'global',
      instance_id: '3'
    }
  }
}

var entry = log.entry(metadata, data)

[stephenplusplus]

@zbjornson mind taking a quick look? Thanks for the idea!

[zbjornson]

Don't have enough time to try it out at the moment, but the API and quick glance at the code look good. Thanks! Let me know if you want me to test before merging, but it looks straightforward enough.

[callmehiphop]

Can we add some system tests for this?

[stephenplusplus]

Yes, good idea. Added!

[coveralls]

Coverage remained the same at 100.0% when pulling 2e3f9b7 on stephenplusplus:spp--1348 into fc7ebb8 on GoogleCloudPlatform:master.

[zbjornson]

Thanks for the fix.

Do you know what version this will come out in -- 0.42.0 or 0.41.3? It's a breaking change and I need to update a dependency accordingly.

[stephenplusplus]

RE: the comment on mlazarov/bunyan-stackdriver#6, we do follow semver. It'll be 0.42.0, although we're backed up for a while (3-7 days) trying to get promises in. It'll also release independently in @google-cloud/[email protected].

[zbjornson]

Thanks.

we do follow semver

Er, right -- I guess because it's pre-1.0.0 breaking changes are allowed. :)

[stephenplusplus]

Pre-1.0, a minor bump signals a breaking change. npm install --save google-cloud saves the value ^0.41.0 in package.json, which is >=0.41.0 && < 0.42.0. Compared to if we were post 1.0, ^1.41.0 would mean >= 1.41.0 && < 2.0.0.