Language Reference: Record types

[BillWagner]

There are a few tasks here:

• Update the "class & structs" article to include a short introductory section on record types.
• Add with to keywords
• Add an article that describes with-ers.
• Add a new language reference article for records. This should include information on the compiler generated members, and how to override them. In addition, it should explain inheritance rules for records, primary constructors, with-ers, and deconstruction methods.
• Update the "Programming Guide->Types->Use and define types" article to mention records.
• Update the "Programming Guide -> Classes and structs" with an article on records. The new article should explain records and when to use them over class types.

[pkulikov]

@BillWagner I would like to add the article for the with expression (into the operators folder). If you're not working on it now, is that fine if I do that?

[BillWagner]

I would like to add the article for the with expression (into the operators folder). If you're not working on it now, is that fine if I do that?

Thanks @pkulikov I appreciate it. I'm not working on this now, so I'd welcome a PR.

[BillWagner]

@pkulikov Are you working on this one? I want to make sure I haven't missed any PRs