Revert xcodebuild invocation logging

Reopens #91. Fixes #161.
Always flush async output before exit

Resolves #162.
Merge pull request #167 from Carthage/fix-version-command

Always flush async output before exit
Merge pull request #165 from Carthage/revert-xcodebuild-command-logging

Revert xcodebuild invocation logging
Merge pull request #153 from Carthage/fix-task-output-race

Refactor to use dispatch_io for tasks, and wait for EOF
Conflicts:
	CarthageKit/Task.swift
Merge pull request #130 from Carthage/travis-ci

Set up Travis CI
Merge pull request #155 from Carthage/fix-empty-build-logs

Fix empty build logs
Conflicts:
	Cartfile
	Cartfile.lock
	Carthage.checkout/ReactiveCocoa
	CarthageKit/Project.swift
Bump plist version to 0.2.2
Merge branch '0.2.2-development'

Conflicts:
	CarthageKit/Project.swift