Support CircleCI 2.0

[dtinth]

CircleCI 2.0, currently in closed beta, supports Docker out-of-the-box. It brings a lot of nice improvements.

However, there are changes in environment variables. The variables CIRCLE_PROJECT_USERNAME and CIRCLE_PROJECT_REPONAME has been removed.

This PR makes codecov-node support running inside CircleCI 2.0.

Output comparison

Before (bash version)

HTTP 400
slug must match pattern ^[\w\-\.]{1,255}\/[\w\-\.]{1,255}$

Coverage data is not uploaded.

Before (node version)

==> Detecting CI Provider
    Circle CI Detected
==> Configuration: 
    Endpoint: https://codecov.io
{ service: 'circleci',
  build: '70.0',
  job: '70.0',
  commit: '7d0aaca1f17ee2c56f4448d7d3c1e35fc838ddab',
  branch: 'my-record',
  pr: undefined,
  slug: 'undefined/undefined',
  package: 'node-v1.0.1' }
...
==> Uploading reports
    HTTP 400
Unable to locate build via CircleCI API. Please upload with the Codecov repository upload token to resolve issue.

Slug is undefined/undefined. Coverage data is not uploaded.

After (node version)

==> Detecting CI Provider
    Circle CI Detected
==> Configuration: 
    Endpoint: https://codecov.io
{ service: 'circleci',
  build: '71.0',
  job: '71.0',
  commit: 'e45d8b7e512e3110501f36c7814eae5c5cb97f26',
  branch: 'my-record',
  pr: undefined,
  slug: 'bemusic/scoreboard',
  package: 'node-v1.0.1' }
...
==> Uploading reports
    Success!
    View report at: https://codecov.io/github/bemusic/scoreboard/commit/e45d8b7e512e3110501f36c7814eae5c5cb97f26

Coverage data uploaded successfully, despite pr being undefined.

[codecov]

Codecov Report

Merging #46 into master will increase coverage by 5.23%.
The diff coverage is 83.33%.

@@            Coverage Diff             @@
##           master      #46      +/-   ##
==========================================
+ Coverage   91.41%   96.65%   +5.23%     
==========================================
  Files          17       17              
  Lines         233      239       +6     
  Branches       44       46       +2     
==========================================
+ Hits          213      231      +18     
+ Misses         20        8      -12

Impacted Files	Coverage Δ
lib/services/circle.js	91.66% <83.33%> (-8.34%)	❌
lib/codecov.js	95.08% <ø> (+2.45%)	✅
lib/detect.js	92.85% <ø> (+21.42%)	✅
lib/services/drone.js	100% <ø> (+27.27%)	✅
lib/services/localGit.js	100% <ø> (+30.76%)	✅

---

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[stevepeak]

Awesome job! 👍