[359385] Override exported/published archive name

In the maven world, it's not uncommon to deploy archives under a different
name than the original one (ex. deploy some-external-library-x.y.z.jar to
WEB-INF/lib/some-external-library.jar instead).

This patch allows 3rd party adopters to override the exported/published archive name
of IClasspathEntry.CPE_LIBRARY type entries by adding an
IClasspathAttribute with the "org.eclipse.jst.component.archivename" key. The value of that
attribute will be read and returned by ClasspathDependencyUtil.getArchiveName(entry)

If the archiveName attribute is not set, the default archive name is
returned.

- I wrote 100 % of the code
- I have the right to contribute the code to Eclipse
- I have updated the header

Signed-off-by: Fred Bricon <fbricon@gmail.com>