NEXUS-5955: Automatic routing should not handle files, except on root
NEXUS-5955: Use once calculated parent path
Attribute handling cleanup.

Changes:
* early detection are attributes handled at all (to save cycles doing things thrown away later)
* cleanup of DefaultAttributesHandler by means of making fields private and final. removal of unused methods
* deprecated ancient StorageFileItemInspector that were operating on java.io.File (and potentially performed catastrophic)
* update core inspectors, made them StorageItemInspector's, reduced size by reusing code from core
* fixed attribute expansion, streamlined logic (detection of unneeded work happens way earlier than before)
* affected UTs updated
No code change, just javadoc.
NEXUS-5963: Do not export nonProxyHosts to system props

As those are in Nexus specific format (regex) and does not
follow the JDK standard for this system property.
NEXUS-5989: AS settings non optional
NEXUS-5963: Adjust UT
Merge pull request #180 from sonatype/NEXUS-5955-autorouting-nofiles

NEXUS-5955: autorouting should not add files to prefixes
Merge pull request #182 from sonatype/attribute-handling-cleanup

Attribute handling cleanup.
Merge pull request #188 from sonatype/NEXUS-5963-non-proxy-hosts

NEXUS-5963: Do not export nonProxyHosts to system props
Merge pull request #189 from sonatype/NEXUS-5989-appsettings-non-optional

NEXUS-5989: AS settings non optional
Merge remote-tracking branch 'origin/master' into NX-19-dynamic-logging