Clean up: Array to buffer as Buffer.fromArray, (not Array.buffer).

[matthewhammer]

As per the discussion with @crusso and @rossberg, Array to buffer should be Buffer.fromArray, not Array.buffer, as was just merged.

Related:

• Add fromArray method to Buffer #368
• Transform an array into a buffer via Array.buffer. #387

[matthewhammer]

@crusso PTAL

[crusso]

Damn, one more iteration - I mistakenly thought the existing toVarArray was called toArrayMut. We are inconsistent in the libs.... but I guess should at least be consistent within the one file.

[matthewhammer]

We are inconsistent in the libs.

Created #391