Removing Meson as way of building dcd, d-scanner, etc

[kinke]

On Wednesday, 12 December 2018 at 12:40:35 UTC, Basile B. wrote:
> Just 3 minutes to install a python version at Travis, that will 
> work to use Meson
>
>     
> https://travis-ci.org/dlang-community/tinyendian/jobs/466966513#L122
>
> That's **silly**.

What's even more silly is building Python manually first, then 
doing `homebrew update` (taking 290 secs!) before brewing ninja 
and Python again (the latter not working). If you just need 
homebrew for Ninja, then do yourself a favor and download the 
prebuilt 
https://github.com/ninja-build/ninja/releases/download/v1.8.2/ninja-mac.zip, that's what we do for LDC CI too. This `homebrew update` is ridiculous, at least for Travis.