Consider renaming Span.context() to spanContext()

[carlosalberto]

I remember in some other SIG seeing users complain that getContext() or context() can be confusing/distracting, and having a longer name could be a good thing.

For your consideration ;)

[dyladan]

Do you mean rename it to span.spanContext() or have some top-level function named spanContext(span)?

[dyladan]

@carlosalberto ?