Ruby 1.8 compatibility for setup and track actions

* Fixes the faulty authorization process under Ruby 1.8 by changing `File.write` semantics (the config file was never written under Ruby 1.8; pretty sure I fixed this before – I must have mangled the changes somewhere downstream).
* Fixes the refactored track actions under Ruby 1.8 by switching to “old style” Hash declaration syntax (NB: the `{symbol: value}` shorthand syntax has been introduced with Ruby 1.9 – Ruby 1.8 compatible code **needs** to use the `{:symbol => value}` syntax.