fix-379 Fixing issue with default value on enums for help text

[ChrisHallett]

https://github.com/commandlineparser/commandline/issues/379

This fixes the issue where the default value for the enum was not being displayed however there are some other issues with this.

Now it will output the enum in help text even if the enum is not included in the command. I believe this would require quite a rework of the input system in order to properly account for this edge case enum issue so not sure if that is actually what is wanted here.