add glcxx and glm submodules

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "glm"]
+	path = glm
+	url = git://github.com/g-truc/glm.git

Makefile

@@ -1,5 +1,6 @@
 FILE := app
 TARGET := $(FILE)
+REPOS := glcxx glm
 
 CCFLAGS := $(shell sdl2-config --cflags)
 ifeq (MINGW,$(findstring MINGW,$(shell uname)))
@@ -12,10 +13,16 @@ endif
 LDFLAGS := $(LIBS) $(shell sdl2-config --libs)
 
 
-all:	$(TARGET)
+all: submodule_init $(TARGET)
 
 $(TARGET): $(FILE).cc
 	$(CXX) -o $(TARGET) $(CCFLAGS) $< $(LDFLAGS)
 
+.PHONY: submodule_init
+submodule_init:
+	@if [ ! -e glcxx ]; then \
+	  git submodule update --init; \
+	fi
+
 clean:
 	-rm -f $(TARGET) *~ *.o

glcxx

@@ -0,0 +1 @@
+Subproject commit e0f6651161cdb03f75ede1bde0e1ac49f097c414

glm

@@ -0,0 +1 @@
+Subproject commit 8f39bb8730d45570384f3156eb0126b835024d69