Import SSKeychain.

SSKeychain is a Cocoapods project which provides handy wrappers around
the iOS keychain (which has a Core Foundation-based API). This import
pulls it in but adjusts all its exported symbols' prefix from "SS" to
"LPSS" to avoid duplicate symbols with any projects that want to link
Calabash and use SSKeychain themselves.
Add "keychain" route handler.

Uses SSKeychain to allow:

    - Querying the keychain for a list of all accounts, all accounts for
      a particular service, or the password for a particular
      service/account combination.
    - Modifying the keychain by deleting accounts.
    - Modifying the keychain by setting the password for a particular
      service/account combination.
Move SSKeychain out of Utils and into Classes
Add SSKeychain's license to NOTICE
Adjust formatting of LPKeychainRoute:

  - 2 space indent
  - Follow recommended method signature style
suppresses compiler warning around CGPathRef vs NSString

compiler warning is generated after enabling modules and automatic
library linking
removed tab from LPKeychainRoute
updating the Xcode project after rebasing and sharing the calabash scheme
enforcing ARC on the keychain query code
documented unexpected 'FAILURE' return value in keychain route
working fix for SSKeychain < iOS 7 and added missing namespacing
set version to 0.9.168.keychain
fixes up the project file after rebase
adding warnings for unreachable code and arc retain cycles
fixing shadowed local variables warnings
added more pedantic warnings
enabled warnings for everything that did throw a warning

going to get this ObjC code into a good shape
removede the Framework target from the visible schemes
rolls back version number to 0.9.163.pre3
Merge pull request #39 from jmoody/fix-pr/jgallagher-add-keychain-support

FIX PR #35:  Add basic keychain support