minor performance tuning;

tuned;

tuned module structure;

tuned names;

imitate internal policy of ByteArrayOutputStream: capacity is doubled after first push;

tuned whitespace;

unused;

Bytes.Builder is unsynchronized, like java.io.OutputBuffer;

notable performance tuning: avoid overhead of higher-order functions;

more efficient equals: avoid somewhat slow sha1_digest (see also 29b761e290c5, 306f273c91ec);