Issue: SPR-14468

Issue: SPR-12431

This change removes most logging at INFO level and also ensures the
amount of information logged at DEBUG level is useful, brief, and
not duplicated.

Also added is custom logging for STOMP frames to ensure very readable
and consise output.

Issue: SPR-11934

spring-messaging is full of unused imports. This commit removes all
unused imports from spring-messaging.

Issue: SPR-11468

Refine semantics of ID and TIMESTAMP headers provided to protected
MessageHeaders constructor.

Refactor internal implementation of MessageHeaderAccessor.

Support mutating headers from a single thread while a message is being
built (e.g. StompDecoder creating message + then adding session id).

Improve immutablity in NativeMessageHeaderAccessor and in
StompHeaderAccessor.

Optimize object creation for initializing messages and subsequent
accessing their headers.

Introduce MessageHeaderAccessorFactory support to enable applying a
common strategies for ID and TIMESTAMP generation to every message.

Add MessageBuilder shortcut factory method for creating messages from
payload and a full-prepared MessageHeaders instance. Also add
equivalent constructors to GenericMessage and ErrorMessage.

Issue: SPR-11468

Update code to have a consistent number of new-line characters after
import statements.

Issue: SPR-10866