Nicer tables episode II (#111)

* Make headrow in tables bold

* Simplify tables markup

- Markup is definitely simpler.
- Will not be built separately in a pdf anymore.
- Fixed some typo as well
- Relatively coherent look
- Can be better, some sizes are relatively arbitrary

* Remove horizontal separation inside tables

Not very nice if you ask me..

* Fix some tables for the ebook

The alignement trick to have nicely alignment on = sign or on unit (g)
used broke the html. Reverting to a less optimal version on pdf while
not breaking the html.

* Simplify table for html output

* Revert "Simplify table for html output"

This reverts commit f85d65adb7.

* Revert pancake table

This way it builds ebook correctly.

book/tables/table-bakers-math-example.tex

@@ -1,12 +1,8 @@
-\input{./vars}
-
-\begin{document}
-\begin{tabular}{lrr}
+\begin{tabular}{@{}lrrr@{}}
 \toprule
-\textbf{Ingredient}    & \multicolumn{1}{l}{\textbf{Percent}} & \multicolumn{1}{l}{\textbf{Calculation}}  \\ \midrule
-1000g flour            & 100\%                                & 1000g of 1000g = 100\%                    \\ \midrule
-600g water             & 60\%                                 & 600g of 1000g = 60\%                      \\ \midrule
-100g sourdough starter & 10\%                                 & 100g of 1000g = 10\%                      \\ \midrule
-20g salt               & 2\%                                  & 20g of 1000g = 2\%                        \\ \bottomrule
+\multicolumn{2}{c}{\thead{Ingredient}}      & \thead{Percentage} & \thead{Calculation} \\ \midrule
+flour             & 1000g &100\%  & 1000g of 1000g = 100\% \\ 
+water             & 600g  & 60\%  &  600g of 1000g =  60\% \\ 
+sourdough starter & 100g  & 10\%  &  100g of 1000g =  10\% \\ 
+salt              &  20g  &  2\%  &   20g of 1000g =   2\% \\ \bottomrule
 \end{tabular}
-\end{document}