Update project for Xcode 10 and Swift 4.1

Add missing parameter name in README

Merge branch 'update-travis-xcode-9'

Use distinct sessions for parallel loop tests to secure results

Update destinations

Update Travis-CI matrix

Bump version to 6.1.0 + Updated Example projects for latest Xcode

Merge pull request #263 from mikelupo/fixRedirect307and308

Better assertion messages to identify failures in tests checking multiple scenarios in loops

[NSURLSessionTests] Moving test class instance variables to a dedicated delegate object for each test needing one

Try fixing random test failure

Fix conversion warning

Fix assertion wording in tests

Update Redirect Tests

Update warnings to Xcode 9