Change "OS X Deployment Target" from 10.10 to 10.9

Travis CI uses 10.9.5

Base32.xcodeproj/project.pbxproj

@@ -539,7 +539,7 @@
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
 				CURRENT_PROJECT_VERSION = 1;
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
-				MACOSX_DEPLOYMENT_TARGET = 10.10;
+				MACOSX_DEPLOYMENT_TARGET = 10.9;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -553,7 +553,7 @@
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
 				CURRENT_PROJECT_VERSION = 1;
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
-				MACOSX_DEPLOYMENT_TARGET = 10.10;
+				MACOSX_DEPLOYMENT_TARGET = 10.9;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";

README.md

@@ -6,7 +6,7 @@ Base32 is a [Base32](https://tools.ietf.org/html/rfc4648) implementation for Swi
 ## Requirements
 
 iOS 8 or later
-OS X 10.10 or later
+OS X 10.9 or later
 
 ## Installation