Raised deployment target to iOS 6.0

#9
Remove uses of dispatch_get_current_queue()

Converts socketQueue to a strong property on connection, which is readonly for request subclasses
Avoid using hard-coded server path in tests
Change test state for cancellations
Add missing <passphrase> to ConnectionInfo-template

Tests do test public key auth
Bump version number in podspec, update to 6.0
Merge pull request #15 from dleehr/deployment-ios6

Deployment ios6