Try to brew reinstall numpy on travis

dstansby · dstansby · commit 76bdd0791600 · 2018-10-24T14:30:54.000+01:00
diff --git a/.travis.yml b/.travis.yml
@@ -105,6 +105,7 @@ before_install: |
     ci/silence brew update
     brew upgrade python
     brew install ffmpeg imagemagick mplayer ccache
+    brew reinstall numpy
     hash -r
     which python
     python --version
