Add a travis config to test building the docs and links

Author: michaelwood

.travis.yml

@@ -0,0 +1,11 @@
+language: python
+
+python: 3.6
+
+install:
+  - "pip install -r requirements.txt"
+
+script:
+  - "cd ./docs/"
+  - "make dirhtml"
+  - "make linkcheck"