closes #149 updates toc syntax from toc2 to :toc: left

- updates toc preferences in user manual toc section
- updates example in attribute section of user manual
- updates toc info in writers guide
- removes toc2 examples
- adds toc left examples
- changes example file names
Merge pull request #150 from graphitefriction/toc2-sidelining

closes #149 updates toc syntax from toc2 to :toc: left