Improve examples packaging

- Removed unused scripts (`build-framework.sh`, `copy-osx-framework.sh`, `replace_framework_path.py`, duplicate `sh build.sh docs`)
- Clean up duplicate framework search paths in all `RealmExamples.xcodeproj` files
- Fixed paths in rubymotion example Rakefile
- Package Swift examples
- Globally replace paths

As a result of these changes, we no longer get warnings when building examples.

Please review @tgoyne @alazier.