Feature!(#64): version flag removal

[andybeet]

Your commits explain the who, what, where and when of these changes. Your code shows the how. You do not need to reiterate this. This PR should complete the big picture by telling the why.

Justification

The code was referencing different versions of the model; the trunk and a 10 year old development model. This was done by using an argument called vesrion_flag in many functions. Since there is only one version now, this is no longer needed. It was removed for all code, docs, rmds, and unit tests

fixes #64

Types of changes

What types of changes does your code introduce? Put an x in the boxes that apply. This will inform version updates

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Other change (if none of the other choices apply)

Reviewer instructions

Run devtools::check() and pkgdown::build_site(). Make sure both run without errors

Formatting

This repo contains an air.toml file that automatically formats code to a set of standards.
It is preferred that contributors and reviewers install the air formatting tool.