Bugfix: Correct links for Xcode download

doc/README_osx.txt

@@ -30,7 +30,7 @@ originally done in toolchain4.
 To complicate things further, all builds must target an Apple SDK. These SDKs
 are free to download, but not redistributable.
 To obtain it, register for a developer account, then download the XCode 6.1.1 dmg:
-https://developer.apple.com/downloads/download.action?path=Developer_Tools/xcode_6.1.1/xcode_6.1.1.dmg
+https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_6.1.1/xcode_6.1.1.dmg
 
 This file is several gigabytes in size, but only a single directory inside is
 needed: Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk

doc/release-process.md

@@ -44,7 +44,7 @@ Release Process
 
  Register and download the Apple SDK: (see OSX Readme for details)
  
- https://developer.apple.com/downloads/download.action?path=Developer_Tools/xcode_6.1.1/xcode_6.1.1.dmg
+ https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_6.1.1/xcode_6.1.1.dmg
  
  Using a Mac, create a tarball for the 10.9 SDK and copy it to the inputs directory: