2.8.5: 'Send Payment' -> 'Pay'; minor fixes.

• Change "Send Payment" button to "Pay". (see #174)
• Minor bug fixes.
• Update card.io library to 5.0.2.

2.8.4: Button for New Account; minor bug fixes

• Add button allowing user to create a new PayPal account.
• Minor bug fixes.
• Update card.io library to 5.0.1.

2.8.3: Fix iOS 6 crash; minor improvements.

• Fix an iOS 6 crash.
• Improve UI for country codes during Phone/PIN login.
• Display currency codes for mixed-currency situations;
  e.g., when choosing between balances in different currencies.
• Minor bug fixes.
• Update card.io library to 5.0.0.

2.8.2: Improve handling of some server errors

• Improve handling of some server errors.
• Minor bug fixes.
• Update card.io library to 4.0.2.

2.8.1: Prevent a rare potential crash

• Prevent a rare crash. (#220)
• Update card.io library to 4.0.1.

2.8.0: Update http header; update card.io

• Update Paypal-Application-Correlation-Id header to PayPal-Client-Metadata-Id,
  and deprecate [PayPalMobile applicationCorrelationIDForEnvironment:] in favor
  of [PayPalMobile clientMetadataID].
• Update card.io library to 4.0.0.

2.7.2: Minor bug fixes

• Minor bug fixes.

2.7.1: further 1Password fixes

• Prevent two MORE potential "duplicate symbol" problems for apps that are also integrating with 1Password.

2.7.0: add rubles; add card.io headers

• Add support for Russian Rubles. issue #223
• Include public header files for card.io, which is contained inside the PayPal iOS SDK,
  for apps that use card.io directly. issue #219
• Minor improvements to Sample App.
• Prevent a few more potential "duplicate symbol" problems for apps that are also integrating with 1Password.
• Update card.io library to 3.10.1.

2.6.1: Minor improvements for select partners

• Minor improvements relevant only to select partners.