Actually fail when test are failing.

The whole tests were under allow-failure (and are failing).
That is to say: some html link don't resolve, and some css is incorrect.

Put at least some of them (spelling) as mandatory.

Author: Carreau

.travis.yml

@@ -5,21 +5,37 @@ rvm:
 matrix:
   allow_failures:
     - rvm: 2.2
+  include:
+    - python: 3
+      env: SPELL=1
+    - rvm: 2.2
+      env: SPELL=0
+
 
 before_install:
  - nvm install node
 
 install:
- - npm install -g csslint
- - pip install codespell --user
- - bundle install
+ - |
+   if [ "$SPELL" = "1" ]
+   then
+     pip install codespell --user
+   else
+     npm install -g csslint
+     bundle install
+   fi
 
 script:
- - bash .travis/cibuild
- - csslint _site/css/gallery.css
- - csslint _site/css/logo-nav.css
- - csslint _site/css/syntax.css
- - codespell -q3 --skip='.git,*.svg,*.json,*.yml,*.lock,_site'
+ - |
+   if [ "$SPELL" = "1" ]
+   then
+     codespell -q3 --skip='.git,*.svg,*.json,*.yml,*.lock,_site'
+   else
+     bash .travis/cibuild
+     csslint _site/css/gallery.css
+     csslint _site/css/logo-nav.css
+     csslint _site/css/syntax.css
+   fi
 
 # branch whitelist, only for GitHub Pages
 

.travis/cibuild

@@ -1,5 +1,7 @@
 #!/usr/bin/env bash
-set -e # halt script on error
+set -Exeuo pipefail # -e halt script on error, -u uset variable is error,
+                  # -o pipefail carry errors up, -x print each line
+                  # -E catch signals
 
 bundle exec jekyll build
 bundle exec htmlproofer ./_site