(build) Add suppport for Xcode 6.1

Update build setting for Xcode 6.0. The final version of Xcode 6.0 does
not include the OS X 10.10 SDK.
(kext) Fix kernel panic related to Comodo Antivirus
(framework) Add support for case-insensitive Objective-C filesystems
Bump version to 2.7.1