Adding travis ci status image to readme.
Doc build now builds nupic and nupic.core.

Update documentation generation script to build docs and publish for
both nupic and nupic.core.
Merge pull request #51 from rhyolight/update-doc-build

Doc build now builds nupic and nupic.core.
Some hooks have a null config. Added a null check.
Merge pull request #52 from rhyolight/empty-hook-config-bugfix

Some hooks have a null config. Added a null check.