Support Alternative Hugo Themes

[reid-spencer]

The generated documentation should not be limited to the generation of a single Hugo theme but support multiple suitable Hugo themes. The goal is not to support all Hugo themes, but a good portion of the documentation oriented themes . Because this will require different Hugo source to be generated for different themes, this is not a trivial request. Consequently, the following themes are recommended in order of implementation:

• GeekDoc (currently implemented in RIDDL)
• Docsy
• GoDocs
• DocDock
• Doks