Meta: enable running the HTML checker on the spec

This ensures that the resulting spec is conformant HTML.

.travis.yml

@@ -6,6 +6,7 @@ addons:
   apt:
     packages:
     - sshpass
+    - oracle-java8-set-default
 
 env:
   global:
@@ -17,3 +18,4 @@ script:
   - npm test
   - cd ..
   - bash ./deploy.sh
+  - curl -O https://sideshowbarker.net/nightlies/jar/vnu.jar && /usr/lib/jvm/java-8-oracle/jre/bin/java -jar vnu.jar --skip-non-html /home/travis/build/whatwg/streams/streams.spec.whatwg.org

index.bs

@@ -184,7 +184,7 @@ until eventually the original source is told to stop producing chunks so fast. T
 the original source according to how fast the chain can process chunks is called <dfn>backpressure</dfn>.
 
 When <a lt="tee a readable stream">teeing</a> a readable stream, the <a>backpressure</a> signals from its two
-<a href="branches of a readable stream tee">branches</a> will aggregate, such that if neither branch is read from, a
+<a lt="branches of a readable stream tee">branches</a> will aggregate, such that if neither branch is read from, a
 backpressure signal will be sent to the <a>underlying source</a> of the original stream.
 
 <!-- TODO when we have writable stream writers

package.json

@@ -5,7 +5,7 @@
     "local-watch": "node ./local-watch.js"
   },
   "devDependencies": {
-    "emu-algify": "^2.1.0",
+    "emu-algify": "^2.2.0",
     "promise-debounce": "^1.0.0"
   }
 }