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Changelog

• Adds DISABLE_BOOTSTRAP_HOOKS env variable.
• Fixes bug when parsing Carthage sem version.
• Uses Cartfile.resolved to check if project uses Carthage #21 (thanks @hzalaz)
• Parameter to enable/disable podspec lint #23 (thanks @hzalaz)
• Adds script to script/common/install_carthage to manually install carthage.
• Adds SwiftLint support.
• Adds linterbot support.
• Removes support for CircleCI.
• Removes brew from main bootstrap script.