Refactoring iOS platform implementation

[armandsLa]

The current iOS platform implementation doesn't follow common Swift best practices. It feels like it's written using Dart conventions, not Swift. Also, there are multiple unused variables, unsafe optional unwrapping, and 2-space indentation (Xcode's default is 4-space). All these things make it hard to work with the iOS side of things(using Xcode) and make PRs. This plugin would really benefit from a refactoring.

I could do this and make a PR, but before I do that, I would like to get confirmation that such a PR would be considered.