Fix GH Pages help link in readme.
Minor: update blog post link to GH clean URLs test.
Minor: update "Making of" post for Hover now.
Neo4j talk: minor tweaks.

- Save one odd remote image locally.
- Tweak two slides' order.
- Fix code snippets.
Node-Neo4j talk: branch off general Neo4j talk.
Node-Neo4j talk: implement differences!
Merge branch 'feature/node-neo4j-talk' into develop
Merge branch 'develop' into gh-pages