Documents should clarify about arrays

[nodakai]

7.2.8 Vector expressions of the language reference refers to the "vector expression" and 7.2.21 Match expressions refers to the "vector pattern". However 8.1.4 Vector, Array, and Slice types of the language reference and the Rust guide refer to the same thing (at least the former) as an "array". It's odd that a "vector expression" creates an "array" rather than a "vector".

There are also dangling <a href="#vector-types"> in the language reference.

Neither the language reference nor the API reference explains which traits an array implements nor what methods are available for it.