Feat: add examples and new exercises caracteristics

tools/examples/chapter/1E_premiers_exercices.tex

@@ -0,0 +1,21 @@
+\documentclass[a4paper,10pt]{article}
+\usepackage{myXsim}
+
+\title{Lorem lorem}
+\tribe{Lorem}
+\date{Mai 2020}
+
+\pagestyle{empty}
+\geometry{left=10mm,right=10mm, top=10mm}
+
+\DeclareExerciseCollection{banque}
+\xsimsetup{
+    step=1,
+}
+
+\begin{document}
+
+\input{exercises.tex}
+\printcollection{banque}
+
+\end{document}