add test for exsheet class

tests/exercises/Makefile

@@ -0,0 +1,7 @@
+SUBDIRS := $(wildcard */.)
+
+all: $(SUBDIRS)
+$(SUBDIRS):
+		$(MAKE) -C $@
+
+.PHONY: all $(SUBDIRS)

tests/exercises/sheet/Makefile

@@ -0,0 +1,3 @@
+test:
+	latexmk -dvi- -pdf -gg -Werror -latexoption=-interaction=nonstopmode test.tex
+	latexmk -c test.tex

tests/exercises/sheet/test.tex

@@ -0,0 +1,13 @@
+\documentclass[ngerman]{mkessler-sheet}
+
+\usepackage{blindtext}
+\usepackage[ngerman]{babel}
+
+\author{Maximilian Keßler}
+\course{Geometrie und Topologie}
+\sheetnumber{7}
+
+\begin{document}
+
+test
+\end{document}