Add support for BS 4.2 switches

[simmerz]

Add :switch value to :custom option for 4.2 switches

[lcreid]

Thanks for this contribution! We really appreciate that you're on top of changes to Bootstrap, and that you help this gem keep up.

Good job with the test coverage!

Please add a line or two in the README.md to show people how to use a switch. There is currently documentation for how to use wrapper_class to render a switch (https://github.com/bootstrap-ruby/bootstrap_form#switches). Please change it to show your syntax.

I appreciate how hard it is to change form_builder.rb without triggering RuboCop offenses, so I'll let your changes to .rubocop_todo.yml go by. :)

Again, thanks for your contribution!

[simmerz]

@lcreid I've updated the documentation to show how to use the new :switch syntax

[simmerz]

@lcreid this PR is now rebased against current master, and I've also refactored the check_box.rb file.

I had a question about double quotes - the .rubocop.yml file enforces double quotes, but the default is single quote unless interpolation is required. Any reason for this particular decision?

[lcreid]

I had a question about double quotes - the .rubocop.yml file enforces double quotes, but the default is single quote unless interpolation is required. Any reason for this particular decision?

I think the simple answer to your question is that both the previous maintainer and myself prefer double quotes. In my case, I like to use contractions when I write, so defaulting to double quotes for strings means I don't have to change the quotes every time I add or take away a contraction from a string. That said, I recognize that there are down sides to both options, so I hope it's not too much of an inconvenience for you.

[lcreid]

Thanks so much for the PR! I really appreciate it that others are keeping up with changes to Bootstrap.

[simmerz]

@lcreid not at all. And regarding double quotes - no inconvenience at all. Always better to ask and to learn than to just accept the status quo though.