Fix code examples in javadoc

The {@code} tag does not automatically insert line breaks, so we need to
include <br/> tags manually to make the javadoc look correct.
NOTICE.txt: use dependency:list instead of resolve

This goal is more in line with the idea of "listing the dependencies"
than "resolve" is, although they both appear to do essentially the same
thing.
NOTICE.txt: expunge SCIFIO deps from imglib

The dependencies transitively required by SCIFIO should not also be
listed under the ImgLib2 entry; they are already enumerated just fine in
the SCIFIO entry.
NOTICE.txt: remove bogus xml-apis dependency

For some reason, Maven thinks that code relying on the javax.xml API
needs an "xml-apis" artifact, but this is not actually true.
NOTICE.txt: fix formatting error

There was a missing newline.