Fix #311
Merge pull request #322 from r-gaia-cs/make-4.0

Fix problem with book "timeline"
Fix link to contribution guidelines
Merge pull request #323 from jkitzes/master

Fix link to contribution guidelines
Add "In" and "Out" before code

Related to issue #289.

Fix problem when PR #252 was merged.
Fix extra line in IPython output template
CSS arrow to mark input and output

**Note**: This is a prototype.

Instead of "In" and "Out" use arrow to mark the input and output
of IPython lessons.

To construct the arrows we only use CSS.
Remove extra space in sql lessons
Updates and corrections to setup
Add publication details for best practices paper Wilson et al
Fix link syntax in glossary
Fix anchor name conversion in book glossary
Merge pull request #328 from jkitzes/fix-book-glossary

[v5] Fix anchor name conversion in book glossary
Fixes for @gvwilson comments
Merge pull request #326 from jkitzes/misc-review

[v5] Review of non-lesson files
Merge pull request #325 from r-gaia-cs/css-arrow

Some fix for IPython Notebook's Template
Bringing in up-to-date instructions for installing Firefox SQLite Manager plugin
Adding link to the VM image and setup instructions
Merge pull request #331 from gvwilson/adding-link-to-vm-image

Adding link to the VM image and setup instructions.
Add title to lessons

Thanks to @gdevenyi for raise this issue.

Close #333.