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• Renames await() to awaitPromise().

• Adds pending promise to FBLPromise's Dot Syntax API and updates parameter type for fulfill:.
• Updates Promises to Swift 5.

• Disables Whole Module Optimization (#98).

• Updates Promises to Xcode 10.2 and integrates with latest SwiftLint checks.

Updates Promises to Swift 4.2.

• Fixes issue 81 where NSError was not being converted to a PromiseError properly.

• Adds retry operator that enables reattempting a task if the promise for that task is initially rejected.
• Sets the APPLICATION_EXTENSION_API_ONLY to YES on the project level and defaults the APPLICATION_EXTENSION_API_ONLY flag on targets.
• Moves SWIFT_VERSION flag from Promise/PromiseTests targets to the Xcode project.
• Applies extension-safe flag for framework targets.

• FBLPromiseCatchBlock renamed to FBLPromiseCatchWorkBlock
• Introduced FBLPromiseErrorIsTimedOut() and FBLPromiseErrorIsValidationFailure() for easier check for predefined FBLPromiseErrorCodes