fixed warnings and added makefile for bench

example/makefile.bench

+CXX	= g++
+CXXFLAGS	= -march=native -Wall -Wextra -Wshadow -pedantic -std=c++11 -pthread -I../include 
+CXX_RELEASE_FLAGS = -O3 -flto
+CXX_DEBUG_FLAGS= -g 
+
+OUTBIN  = bench
+
+all: bench.cpp
+	$(CXX) bench.cpp -o $(OUTBIN) $(CXXFLAGS) $(CXX_RELEASE_FLAGS)
+	
+
+debug: bench.cpp
+	$(CXX) bench.cpp -o $(OUTBIN)-debug $(CXXFLAGS) $(CXX_DEBUG_FLAGS)
+
+
+
+clean:
+	rm -f *.txt $(OUTBIN) $(OUTBIN)-debug
+
+
+rebuild: clean all
+rebuild-debug: clean debug
+
+