SemaphoreCI transition: only run OSX jobs on Travis

[wilzbach]

• Run DMD with MODEL=32 on Semaphore
• Remove LDC with MODEL=32
• Remove now unused multilib packages

[dlang-bot]

Thanks for your pull request, @wilzbach!

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[jacob-carlborg]

LGTM 👌.

[wilzbach]

FYI: I updated the Semaphore config accordingly:

[ibuclaw]

@wilzbach - force rebase for retriggering semaphore builds?

[ibuclaw]

Also, it's about time that semaphoreci is made as a "Required" CI for pulls.

[wilzbach]

@wilzbach - force rebase for retriggering semaphore builds?

The build failed. I just restarted it.
FYI: was experimenting with the x86 DMD build (i.e. DMD 64-bit is used to bootstrapped DMD 32-bit). It seems all that was necessary is this line:

> sudo apt-get update && sudo apt-get install -y g++-multilib libcurl3-gnutls:i386

It sucks a bit that SemaphoreCI only supports organisations in the paid mode, but maybe @CyberShadow can add the usual candidates from https://github.com/orgs/dlang/teams/team-dmd/members for now?
I still have on my list to let the dlang-bot recognize a "rebase" or "squash" label which would make life a bit easier - maybe I finally get to finish this over the next days.

[wilzbach]

Also, it's about time that semaphoreci is made as a "Required" CI for pulls.

OK let's try this for one week. If something goes wrong we can immediately disable it.

[JinShil]

As @WalterBright pointed out in another PR, is it not possible see the stderr and stdout output of the test?

I'm an idiot.

[wilzbach]

As @WalterBright pointed out in another PR, is it not possible see the stderr and stdout output of the test?

1. Click on a job

2. Expand the test