[BEAM-4046] Remove old project name mappings.

[lukecwik]

This finishes the migration to use the canonical gradle directory layout / project naming.

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Post-Commit Tests Status (on master branch)

Lang	SDK	Apex	Dataflow	Flink	Gearpump	Samza	Spark
Go		---	---		---	---
Java
Python		---			---	---

Pre-Commit Tests Status (on master branch)

---	Java	Python	Go	Website
Non-portable
Portable	---		---	---

See .test-infra/jenkins/README for trigger phrase, status and link of all Jenkins jobs.

[lukecwik]

R: @adude3141 @udim

[lukecwik]

Run Spotless PreCommit

[lukecwik]

Run RAT PreCommit

[adude3141]

Although I d really love to get that in, I think we are not yet in the state to remove that translation layer.

Rationale for introducing this layer was to give users the chance to adapt to the new style. I believe we should at least prepare our documentation (e.g. cwiki) to reflect the new style, which was not done yet.

Unfortunately I did not take care to get edit rights for cwiki yet, but I d volunteer to look into this.

wdyt?

[lukecwik]

SGTM, I granted you access to the cwiki.

[adude3141]

Adapted https://cwiki.apache.org/confluence/display/BEAM/Apache+Beam to use the canonical gradle directory layout / project naming.

So currently both, beam git repo and beam cwiki should be migrated.

I guess, there will be resources still referecing the old style, which are unfortunately not on our control, eg. stack overflow, blogs etc. But are there any further resources under our control missing migration?

[lukecwik]

Not that I'm aware of.

[stale]

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[stale]

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[adude3141]

Now another quarter passed... guess we should finally get this done.

[stale]

This pull request is no longer marked as stale.

[lukecwik]

I rebased this on top of master.

[adude3141]

LGTM