Target OS X Yosemite (10.10) when building lib

* In line with UI
* Supports more users :-)

lib/Makefile

+ifeq ($(OS),Windows_NT)
+    detected_OS := Windows
+else
+    detected_OS := $(shell uname -s)
+endif
+
+ifeq ($(detected_OS),Darwin)
+    CXXFLAGS += -mmacosx-version-min=10.10
+endif
+
+
 all: libantenna.a antenna_lib.o antenna_main
 
 antenna_main: antenna_lib.o antenna_main.cpp antenna_lib.h
-	g++ -o antenna_main antenna_main.cpp antenna_lib.o -lm
+	g++ $(CXXFLAGS) -o antenna_main antenna_main.cpp antenna_lib.o -lm
 
 antenna_lib.o: antenna_lib.cpp antenna_lib.h
-	g++ -c antenna_lib.cpp
+	g++ $(CXXFLAGS) -c antenna_lib.cpp
 
 libantenna.a: antenna_lib.o
 	ar rcs libantenna.a antenna_lib.o