Help Examples should be shell-sensitive

**Is your feature request related to a problem? Please describe.**
By convention, our examples are written to by platform agnostic. However, when we do use any kind of shell-specific syntax, we use bash syntax. The example doesn't identify this and thus CMD or Powershell users are often confused when the example doesn't work.

**Describe the solution you'd like**
We have a `supported_profiles` kwarg for examples. It might make sense to have a `supported_shell` kwarg to identify those examples that use shell-specific syntax. If the user is using an incompatible shell, the example will simply not be displayed.

In this way, we could simply add versions of the example that work for different shells.