Add project structure and write part of introduction

Makefile

@@ -0,0 +1,16 @@
+DOCUMENTS := $(patsubst src/%/main.tex,build/%.pdf,$(wildcard src/*/main.tex))
+
+.PHONY: all
+all: $(DOCUMENTS)
+
+build/%.pdf: src/%/main.tex build/prepared
+	latexmk $<
+	mv build/main.pdf $@
+
+build/prepared:
+	mkdir -p build
+	touch build/prepared
+
+.PHONY: clean
+clean:
+	rm -rf build