Use Siunitx package for dealing with units (#129)

It is complicated :
[1] The International System of Units (si), https://www.bipm.org/en/
measurement-units/.
[2] International System of Units from nist, http://physics.nist.gov/cuu/Units/
index.html.

And one will never get it right (space or not, half-space?) nor
consistent so using that instead.

I am not sure how times and hours, when to write digits and when in
letter so I did not change much..

Did not touch the tables as ebooks on github actions seems to break when
you look at them funny.

Co-authored-by: Cedric <ced@awase.ostal>

book/basics/how-sourdough-works.tex

@@ -91,7 +91,7 @@ packaging of the bread you buy. If you find \emph{malt} in the list of
 ingredients, chances are this strategy was used.
 
 Note that there are actually two categories of malt. One is \emph{enzymatically
-active malt}, which has not been heated to above 70°C, where the amylases begin
+active malt}, which has not been heated to above  \qty{70}{\degreeCelsius}, where the amylases begin
 to degrade. The other is \emph{inactive malt}, which has been heated to higher
 temperatures and thus has no impact on your flour.
 
@@ -122,7 +122,7 @@ in readying amino acids for the germ.
 
 Here's another interesting experiment you can try to better visualize the
 importance of protease: Make a fast-proofing dough using a large quantity
-of active dry yeast. In one to two hours, your dough should have leavened and
+of active dry yeast. In 1--2~hours, your dough should have leavened and
 increased in size. Bake it, then examine the crumb structure. You should see
 that it's quite dense and nowhere near as fluffy as it could have been. That's
 because the protease enzyme wasn't given enough time to do its job.
@@ -140,7 +140,7 @@ Aside from using great ingredients, the slow fermentation process is one of the
 main reasons Neapolitan pizza tastes so great: because the protease creates an
 extensible, easy-to-inflate dough, a soft and airy edge is achieved.
 
-Because the fermentation process typically takes longer than eight hours, a
+Because the fermentation process typically takes longer than 8~hours, a
 flour with a higher gluten content should be used. This gives the dough more
 time to be broken down by the protease without negatively affecting its
 elasticity. If you were to use a weaker flour, you might end up with a dough
@@ -206,7 +206,7 @@ tweak just by adjusting the speed of your dough's fermentation.
 
 Yeasts are single-celled microorganisms belonging to the fungi kingdom, and
 spores that are hundreds of millions of years old have been identified by
-scientists. There are a wide variety of species --- so far, about 1,500 have been
+scientists. There are a wide variety of species --- so far, about \num{1500} have been
 identified. Unlike other members of the fungi kingdom such as mold, yeasts do
 not ordinarily create a mycelium network~\cite{molecular+mechanisms+yeast}.\footnote{For
 one interesting exception, skip ahead to the end of this section.}
@@ -234,8 +234,8 @@ When oxygen is not present, their metabolism changes to produce alcoholic
 compounds~\cite{effects+oxygen+yeast+growth}.
 
 The temperatures at which yeast grows varies. Some yeasts, such as
-\emph{Leucosporidium frigidum}, do best at temperatures ranging from -2°C to
-20°C, while others prefer higher temperatures. In general, the warmer the
+\emph{Leucosporidium frigidum}, do best at temperatures ranging from \qty{-2}{\degreeCelsius} to
+ \qty{20}{\degreeCelsius}, while others prefer higher temperatures. In general, the warmer the
 environment, the faster the yeast's metabolism. The variety of yeast
 that you cultivate in your sourdough starter should work best within the range
 of temperatures where the grain was grown and harvested. So, if you are from a
@@ -362,7 +362,7 @@ sometimes benefit each other, but not always. Yeast, for example, tolerate the
 acidic environment created by the surrounding bacteria and are thus protected
 from other pathogens. Meanwhile, however, other research demonstrates that both
 types of microorganisms produce compounds that prevent the other from
-metabolizing food---an interesting observation, by the way, as it could help to
+metabolizing food --- an interesting observation, by the way, as it could help to
 identify additional antibiotics or fungicides~\cite{mold+lactic+acid+bacteria}.
 
 In the past, I've tried cultivating mushrooms and observed the mycelium
@@ -421,8 +421,8 @@ temperature used to create your starter because you've already selected for
 bacteria that thrive under that condition.
 
 In one noteworthy experiment, scientists examined the lactic acid bacteria
-found on corn leaves. They lowered the ambient temperature from 20--25°C to around
-5--10°C and afterward observed varieties of the bacteria that had never been
+found on corn leaves. They lowered the ambient temperature from \qtyrange{20}{25}{\degreeCelsius} to around
+\qtyrange{5}{10}{\degreeCelsius} and afterward observed varieties of the bacteria that had never been
 seen before~\cite{temperature+bacteria+corn}, confirming that there is, in
 fact, a large variety of bacterial strains living on the leaves of the plant.