allow Xcode to auto-update openFrameworksLib.xcodeproj

Set last upgrade check to Xcode 6.0.1
Set "Build Active Architecture Only" to YES for Debug
allow xcode to auto-update osx project template

Add "Code Sign on Copy"
Set last upgrade check to Xcode 6.0.1
Set Architectures to 32-bit (from "native")
Set "Build Active Architecture Only" to YES for Debug
Merge pull request #3360 from admsyn/fix-update-xcode-proj

Allow xcode 6.0.1 to update the OF project and the OSX project template