version of gem read dynamically from Gemfile

:clipboard: **Description**

Seeing that it is possible to read the version of a node dependency from a github repo's `package.json` using https://img.shields.io/github/package-json/dependency-version/[user]/[repo]/[dependency] (and I saw that this even works for `devDependencies` by add `dev` to the path: https://img.shields.io/github/package-json/dependency-version/[user]/[repo]/dev/[dependency]), it would be nice to have a similar possibility for reading the version of a Gem from a Gemfile, using something like:

https://img.shields.io/github/gemfile/dependency-version/[user]/[repo]/[gem]

Gemfiles can group together **dev dependencies** or **test dependencies** by defining the `development` and `test` groups, it would be nice to also read from these groups, perhaps using a path similarly to the package-json path:

https://img.shields.io/github/gemfile/dependency-version/[user]/[repo]/development/[gem]

https://img.shields.io/github/gemfile/dependency-version/[user]/[repo]/test/[gem]

I can see there being some complexity involved, since some gems might be grouped as both `development` and `test`. You can have both separate groups and combined groups.

And other than reading from Gemfiles, it would be nice to be able to read the **Ruby** version defined in the `.ruby-version` file, perhaps something like this:

https://img.shields.io/github/ruby-version/[user]/[repo]/

Likewise it would be nice to have a similar route for reading the **Node** version for a project from the `.node-version` or `.nvmrc` files, something like:

https://img.shields.io/github/node-version/[user]/[repo]/

I've poked around on the shields.io website but I didn't seem to find any routes like the ones mentioned here?

Start by reviewing the existing package.json dependency-version badge route, then compare the requested Gemfile, .ruby-version, .node-version, and .nvmrc inputs. Define the route behavior for normal, development, and test dependencies, including gems in multiple groups, and verify the proposed Ruby and Node version badges before considering the feature complete.

Written by the indexing model from the issue text.