docs: breaking change

BREAKING CHANGE: If you run travis_after_all and travis-after-all at the same
time they'll keep waiting for each other until forever. You have to apply
this patch to your `.travis.yml`.

```diff
---
 .travis.yml | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index a5fbddb..c76091b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,9 +14,6 @@ before_install:
 - npm i -g npm@^2.0.0
 before_script:
 - npm prune
-- curl -Lo travis_after_all.py https://git.io/vLSON
 after_success:
-- python travis_after_all.py
-- export $(cat .to_export_back)
 - npm run semantic-release
--
```