Readd --pre to 3.5

jenshnielsen · jenshnielsen · commit 54ddbe5f425d · 2015-09-15T11:53:52.000+02:00
Needed because the wheelhouse does not correctly handle missing versions
diff --git a/.travis.yml b/.travis.yml
@@ -45,6 +45,7 @@ matrix:
     - python: 2.7
       env: BUILD_DOCS=true MOCK=mock
     - python: "3.5.0rc4"
+      env: PRE=--pre
     - python: "nightly"
       env: PRE=--pre
   allow_failures:
