Merge tag '1.5.0' into develop

v1.5.0

- New: per-device config files
- New: deviceSetup() deviceTeardown() support
- New: environment safeguarding
- New: shutdown hooks
- New: iframe support in browsers
- New: multi-window support in browsers
- New: can close browser windows without terminating the browser session
- New: 'show-environment' command
- New: Sauce Labs devices supported out of the box
- New: storyplayer.phar (experimental)
- Fix: default environment is never the FQDN
- Fix: tryTo() works once again
Fix: Update README to point to 1.5.0
Fix: update the version number
Version bump for bugfix release
Merge branch 'release/1.5.1'