Guide: edits to CLI project.ptx description

[Alex-Jordan]

Yesterday I updated a very old project, our calculus lab manual. Remember things like autoname="no"? Captions on a sidebyside? I hit several blasts from the past.

Anyway I had some readability trouble with the guide's section on the project.ptx file. Totally my own issues with failing to read everything all together and instead only reading the snippets I thought I could get away with. But I thought some editing could help other people who read like I sometimes do. Roughly the changes here are all:

• correct some typos
• state some critical detail at the opening of a section, not only at the end
• attribute values inside a <c> instead of in plain text double quotes
• some consistency applied to the attribute descriptions, and move "required if" conditions close to the start of the description

[rbeezer]

Thanks for the clean-up!

I think @autoname is still documented in the sample article! :-(