Granular flake support

[MylesBorins]

Closes #54

originally flakyness could only be set as a boolean.

Now it can be set in multiple ways

As a boolean: true | false

As a string: version | platform | arch | platform-arch
e.g 'v5' | 'darwin' | 'x86' | 'darwin-x86'

As an array of targets: ['v5', 'v4', 'x86']

As an object for more granular control:

{
  'v4': ['darwin', 'arm'],
  'v5': true,
  'v6': 'linux'
}

Or even as an array of objects:

[{ 'linux': 'v6' }, {'darwin': ['v4', 'v5', 'v6']}]

There is potentially too much granularity here... but it all works
and it is all tested with 100% code coverage so why not.

[MylesBorins]

ci: https://ci.nodejs.org/view/Node.js-citgm/job/thealphanerd-smoker/220/

[MylesBorins]

/cc @orangemocha @mhdawson @jasnell

[MylesBorins]

One more run on master, should be green --> https://ci.nodejs.org/view/Node.js-citgm/job/thealphanerd-smoker/222/

[jasnell]

LGTM

[mhdawson]

A bit late on my part to comment but here it goes anyway. Overall looks good, but I think this will only works on a subset of linux distros:

 var lsb = require('dotenv').config({path: '/etc/lsb-release', silent: true});

for example on a ppc rhel machine it looks like:

bash-4.1$ cat /etc/lsb-release
LSB_VERSION=base-4.0-noarch:base-4.0-ppc64:core-4.0-noarch:core-4.0-ppc64:graphics-4.0-noarch:graphics-4.0-ppc64:printing-4.0-noarch:printing-4.0-ppc64

as opposed to on an ubuntu machine:

mhdawson@duv-aurora:~/pulls/api/node-eps$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.2 LTS"

[MylesBorins]

@mhdawson the current logic will make it essentially a no-op on ppc. We are able to already get the specific ppc information from arch and simply filter by ppc, so I'm not sure if there is anything actionable to do with what we've got.

Totally open to adding anything that can improve granularity / control on ppc

[mhdawson]

@thealphanerd I don't think its limited to ppc, I believe its likely RHEL on x86 and possibly SLES will have contents different than we see on ubuntu.

I checked on one of our SLES 12 x86 and one of our RHEL 71 machines and I don't see /etc/lsb-release at all.

On one x86 SLES 11 machines I see:

dnv-auria:/> cat /etc/lsb-release
LSB_VERSION="core-2.0-noarch:core-3.2-noarch:core-4.0-noarch:core-2.0-x86_64:core-3.2-x86_64:core-4.0-x86_64"

So my more general point is that even on x86 I don't think it will give use what you were hoping for.