* master:
  Updating Cocoapods and Carthage installation instructions
  Add notes related to 2.5.0
  Fix some low-hanging swiftlint errors.
  Update README with attribute deserialization examples, as well as remove deprecated `attributes` dictionary usage.
  replace `try!` with `try` to prevent runtime assertion crashes when encountering an error while deserializing lazily-loaded XML
  Add test for lazy parsing of attributes.
  Add computed param to replace deprecated attributes[] dictionary to maintain API compatibility until Swift3 update. Add unit tests for both attribute access APIs.
  Add automatic deserialization of XML Attributes through the XMLIndexer and XMLElement `value(ofAttribute:)` API.
  Get Travis CI build working
  Switch to using XCTest for specs
  Version bump to 2.4.0
  make XMLElement children property public and add "xml parsing - should be able to iterate over mixed content" test
  Add XMLAttribute type w/ text deserialization