[NX-232] Staging upload
move org.sonatype.nexus.log -> nexus-log-api module
Extract nexus-log-api into module, move impls to org.sonatype.nexus.internal.log
Drop notifications api, this was used only for auto-[un]block notifications.
Update location of default logback.properties resource
Split up the internal details of the org.sonatype.nexus.email package.
Remove use of internal configuration model in validator api.
Drop legacy UI support.
apply header
properly pass username from config
Merge branch 'master' into split-email-internal
[NX-232] Validate form on load
Merge pull request #580 from sonatype/extract-nexus-log-api

REVIEW: Extract nexus log api
Merge branch 'master' into remove-notifications

Conflicts:
	plugins/rapture/nexus-coreui-plugin/src/main/java/org/sonatype/nexus/coreui/NotificationSettingsComponent.groovy
Merge pull request #582 from sonatype/remove-notifications

REVIEW: Drop org.sonatype.nexus.notifications api
Merge pull request #583 from sonatype/split-email-internal

REVIEW: Split up the internal details of the org.sonatype.nexus.email package.
[NEXUS-6653] When expire proxy-caches for path=/ do not walk, generate a unique invalidation-token,
when checking if storage-item is old, treat item as expired if invalidation-token does not match.
Merge branch 'master' into NX-232-staging-upload-ui
Drop NX.coreui.controller.NotificationSettings
Merge branch 'master' into NX-232-staging-upload-ui
Merge pull request #584 from sonatype/NX-232-staging-upload-ui

REVIEW: [NX-232] Staging (bundle) upload UI
@Qualifier is not needed on this marker annotation, as it's just annotating methods to be intercepted and not actual components