Review starter types (#238)

* Correct wording, category for starter conversion

- Now a flowchart (and a renamed label)
- More explicit wording as per
https://github.com/hendricius/the-sourdough-framework/issues/234

* Fix warnings from make check

The one I am 100% sure are mistakes

* Review starter type chapter

- Add some new sections
- fine tune tables
- some typos/new paragraphs

* Fix typos in sourdough starter types

* Simplify liquid conversion flowchart

* Simplify stiff conversion flowchart

* Fine tune liquid conversion flowchart

* Update some of the images

* Improve explanation of conversion

* Update explanation for stiff starter conversion

* Update fall note

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Co-authored-by: Hendrik Kleinwaechter <hendrik.kleinwaechter@gmail.com>

book/figures/flowcharts_tikz.tex

@@ -1,5 +1,6 @@
 \tikzstyle{every picture}+=[font=\footnotesize\sffamily]
-\usetikzlibrary{shapes, arrows, decorations.pathreplacing,calligraphy, calligraphy}
+\usetikzlibrary{calc, shapes, arrows, decorations.pathreplacing, calligraphy,
+                calligraphy}
 \tikzstyle{decision} = [diamond, draw=codeblack, fill=codeblack, text=white,
     text width=4.5em, text badly centered, node distance=3cm, inner sep=0pt,
     line width=2mm]
@@ -23,3 +24,4 @@
 \tikzstyle{BC} =  [decorate,  % Brace Calligraphic
                  decoration={calligraphic brace, amplitude=3mm, raise=1mm},
                  very thick, pen colour={black} ]
+\tikzstyle{loop} = [arc, draw=codeblack, line width=0.4mm]