Snapshot provides redo position.
Merge remote-tracking branch 'remotes/origin/master' into stream
Inherit docs from parent interface.
Closed index reports itself as unmodifiable.
Merge remote-tracking branch 'remotes/origin/master' into stream

Conflicts:
	src/main/java/org/cojen/tupl/Index.java
Documented key range checks.
Merge remote-tracking branch 'remotes/origin/master' into stream
Add throws javadoc comments.
Remove unnecessary assignment.
Eliminate unnecessary seeks.
Add internal method to insert entries at the lowest or highest position.
Merge remote-tracking branch 'remotes/origin/master' into stream

Conflicts:
	src/main/java/org/cojen/tupl/TreeCursor.java