chore: release 2.0.0

[feywind]

🤖 I have created a release *beep* *boop*

2.0.0 (2020-05-19)

⚠ BREAKING CHANGES

• dropp support for custom promises (chore!: drop support for custom promises #970)
• convert to typescript (build!: convert to typescript #923)
• deps: update dependency @google-cloud/projectify to v2 (fix(deps)!: update dependency @google-cloud/projectify to v2 #929)

Bug Fixes

• docs: link to correct gaxOptions docs (#999) (312e318)
• regen protos and tests, formatting (#991) (e350b97)
• remove eslint, update gax, fix generated protos, run the generator (#955) (544a061)
• remove unused dependencies (#998) (7b242a3)
• close: ensure in-flight messages are drained (#952) (93a2bd7)
• deps: update dependency @google-cloud/paginator to v3 (#931) (b621854)
• deps: update dependency @google-cloud/precise-date to v2 (#934) (72b8d78)
• deps: update dependency @google-cloud/projectify to v2 (#929) (45d9880)
• deps: update dependency @google-cloud/promisify to v2 (#928) (3819877)
• deps: update dependency google-auth-library to v6 (#935) (73fc887)

Build System

• convert to typescript (#923) (2fc68ba)

Miscellaneous Chores

• dropp support for custom promises (#970) (df462d3)

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This PR was generated with Release Please.

[codecov]

Codecov Report

Merging #989 into master will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #989      +/-   ##
==========================================
+ Coverage   95.17%   95.21%   +0.03%     
==========================================
  Files          22       22              
  Lines       10615    10615              
  Branches      466      466              
==========================================
+ Hits        10103    10107       +4     
+ Misses        509      505       -4     
  Partials        3        3              

Impacted Files	Coverage Δ
src/pubsub.ts	99.50% <0.00%> (+0.16%)	⬆️
src/subscriber.ts	99.79% <0.00%> (+0.20%)	⬆️
src/message-stream.ts	98.70% <0.00%> (+0.25%)	⬆️

---

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[feywind]

Because I haven't gotten my release-please changes merged yet, this one has to be done by me running my updated version locally. I want to get that in soon, but for now I'll probably need to get someone else to review since it looks like it is my PR.

[feywind]

The changelog is busted on this, probably because of my earlier testing shenanigans. I'm going to just close this and re-open a new one.