Issue #63. If running Command Line Tool app terminateNotification isn't called, so use atexit_b instead
Merge pull request #184 from dvor/issue63--flush-loggers-in-command-line-tool-app

Fixing issue #63.
Bump pod spec version
Improve system version detection over #171

When building against iOS 6 SDK `NSFoundationVersionNumber_iOS_6_0` and `NSFoundationVersionNumber_iOS_6_1` may not be defined.

Replaces #186.
Merge pull request #187 from rivera-ernesto/ios_version_detection

Improve iOS system version detection over #171
Updated podspec for version 1.6.5.1 (patch for Xcode 4)