Removing -j numcores

Makefile

@@ -10,7 +10,7 @@ K := $(foreach exec,$(EXECUTABLES),\
         $(if $(shell which $(exec)),some string,$(error "No $(exec) in PATH)))
 
 doc:
-	cd Doc;$(MAKE) -j ${numCores} all
+	cd Doc;$(MAKE) all
 
 exam:
 	cd Klausuren/Sd1;$(MAKE) -j ${numCores} all