Fix the C++ example (#41)

- Build with -pthread
- Detach the thread to avoid std::thread exception
- Remove __RASPBIAN__ check (it's not defined by the on-Pi compiler)

deps/examples/cpp-multiCameraServer/Makefile

@@ -12,7 +12,7 @@ clean:
 	rm ${EXE} *.o
 
 ${EXE}: main.o
-	${CXX} -o $@ $< -L/usr/local/frc/lib -lcameraserver -lcscore -lntcore -lwpiutil
+	${CXX} -pthread -o $@ $< -L/usr/local/frc/lib -lcameraserver -lcscore -lntcore -lwpiutil
 
 .cpp.o:
-	${CXX} -O -c -o $@ -I/usr/local/frc/include $<
+	${CXX} -pthread -O -c -o $@ -I/usr/local/frc/include $<