Develop 4.0 bridgeable

[dtopouza]

Title: Add bridgeable() function and unit tests.

Key Features:

• Add R/bridgeable.R function
• Add tests/testthat/test-bridgeable.R with basic unit tests for bridgeable()

Checklist

• [x] Make sure you are requesting to pull a feature/bugfix branch (right side). This should not be main or develop.
• [x] Make sure you are make a pull request against either main or develop (left side). (Requesting to main should be reserved for bugfixes and new releases)
• [x] Add or update unit tests (if applicable)
• [x] Check your code with any unit tests (Run devtools::check() locally)
• [ ] Add neccessary documentation (if applicable)

Type of changes

What type of changes does your code introduce? Put an x in the boxes that apply

• [ ] Bugfix (non-breaking change which fixes an issue) (link the issue on the right)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Code style update (formatting, renaming)
• [ ] Documentation Update
• [ ] Other (explain)

[klevdiamanti]

I will start a new branch from "develop_4.0_bridgeable" called "develop_4.0_bridgeable_v2", and merge the updated "develop_4.0" from #440 to it. And then re-work the bridgeable code. Hope this is ok.

[klevdiamanti]

I suggest we close this PR as #447 supersedes it.