Improve the docs building process (#834)

* Add a script to automatically build and push docs

This script will checkout the repo in the `docs` branch, then build the
docs locally, copy it to that repo, commit and push. It is designed to
be used in conjunction with Travis.

* Add unencrypted deploy keys to the gitignore

* Make Travis automatically execute the deploy script

* Add the encrypted deploy key

* Update the .travis.yml with the necessary information

.travis.yml

@@ -5,3 +5,9 @@ cache:
   directories:
     - node_modules
 install: npm install
+script: bash ./docs/deploy/deploy.sh
+env:
+  global:
+    - ENCRYPTION_LABEL: "be0b3b658a36"
+    - COMMIT_AUTHOR_EMAIL: "amishshah.2k@gmail.com"
+