[tlbuild] Support for musl

[Henri]

On Wed, 2018-01-24 at 13:43 +0900, Norbert Preining wrote:
> > 
> > Is this possible with the docker stuff, too?
> It is, just install findutils and run it ;-)
> 
> I adjusted the travis file - reading the log it seems that the
>   cd texlive
> is not necessary in the docker command, though.
> 
> See current .travis.yml on github

Indeed, "cd texlive" is not necessary because "-w /texlive" in the Docker command already sets the
working directory.

Protip:  You don't have to repeat before_script in both jobs.  Just move it outside the matrix.
https://github.com/hmenke/texlive-source/commit/f37910f7e945d9eb3e6d72c9683709712e09b841

I'm pretty sure this should work but better let the tests complete first:
https://travis-ci.org/hmenke/texlive-source/builds/332673389

> 
> Norbert
> 
> --
> PREINING Norbert                               http://www.preining.info
> Accelia Inc.     +    JAIST     +    TeX Live     +    Debian Developer
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