slide IDs should be valid html
Merge pull request #197 from binford2k/generate_valid_is

slide IDs should be valid html
This adds the capability for personal notes

In some use cases, it's nice to have the ability to add personal notes
to be displayed alongside the built in presenter notes. This commit
allows you to do this. Just create a short markdown file in `_notes` that
matches the complete pathname of the slide that you'd like to add notes to.

You may need to empty your browser cache before this displays properly
for the first time.
Merge pull request #198 from binford2k/feature/personal_notes

This adds the capability for personal notes
version bump