Add explicit casts to external C function to make example compile with stricter compiler flags.
Working through Chapter 2 issues

When removing todo items I either fix them or at least add them as issues in GitHub.
Ooops, forgot to add these with last commit
Clarified one legend
Removed all existing todo items in chapter 2

In some cases, these were addressed and in others they were simply moved to GitHub.
Reordered todo

@dietmarw pointed out that it is very bad to have an index item followed by
a todo.  So I reversed the order.  He submitted a pull request for this but
since it wouldn't merge automatically, I just did it myself.

As such, this closes #190.
Added missing table

This closes #187
Updated CHANGELOG and minor CSS fix
Added discussion of the smooth operator

This closes #187
Adding some models to try and demonstrate the effect of noEvent
Adding a link to the Lato font

I'm not using it yet, just wanted it available
Adding some discussion about events vs. performance

So far, I'm not getting the results I was hoping for.  I need to refine these examples and,
of course, make sure the analysis correct.
Got a good example of the impact of noEvent
Fixed changes for chapter 2 and 3
Worked on making heat transfer formulations more consistent

This closes #150.
Give credit to Lionel for helping to improve this section
Creating a Dockerfile for a build container
Fixing something I overlooked in chapter 2
Made some changes to address issue #15

Not sure if this is the final word on fonts, but it is definitely an improvement over the
headings we had before.
Updated translation status