added comments to Makefile

Makefile

@@ -2,15 +2,18 @@ MODULES:=java/dummy
 #cpp/greedy
 #rust/2opt
 
+# Points to the location where we will get the TSP problem data from
 TSPLIB_MIRROR:=http://comopt.ifi.uni-heidelberg.de/software/TSPLIB95
 TSPLIB:=$(TSPLIB_MIRROR)/tsp
 TSPLIB_XML:=$(TSPLIB_MIRROR)/XML-TSPLIB/instances
 TSPLIB_280:=a280
 
+# Defining the location where the data will be saved
 DATA_DIR:=data
-
 TEST_FILE:=$(CURDIR)/$(DATA_DIR)/$(TSPLIB_280)
 
+# Tells make to run these rules regardless of whether or not a file with 
+# these names exist
 .PHONY: compile run clean depclean $(MODULES)
 
 all:	$(DATA_DIR) 
@@ -23,9 +26,11 @@ clean:
 		$(MAKE) -C $$mod clean; \
 	done
 
+# Removes the data directory
 depclean: clean
 	rm -rf $(DATA_DIR)
 
+# Initializes the data directory: downloads the TSP data and unzips and such
 $(DATA_DIR):
 	mkdir $(DATA_DIR)
 	wget -P $(DATA_DIR) $(TSPLIB)/$(TSPLIB_280).tsp.gz