Changes stemming for weekend talk with JD

Loosely relates to local storage improvements

Changes:
* Cleared up nullability of storage context: local is never null, remote is never null (unless a bug, hosted repo casted to Proxy and invoked getter for remote)
* Cleaned up "lazy" creation of storage context, caches and other stuff in Repositories (hosted and proxy)
* Moved thread management from registry (made it simpler) to proxy repo who's thread it is (as we introduced dispose)
* Added Override annotations for early warning (to ease refactoring)
* Removed unused setters from Repository interface
* Removed unused and unfinished task filtering
Shuffled around when things needing repo ID are created.

Originally, it was at wrong place, as no configuration existed yet
for the repo
UT used "illegal" mocks, having null storage context.
Stopping thread always.

As dispose is invoked only when repo is removed
from the system, but in tests, when JVM is not stopped
but new instance of nx is started, old threads left in
dandling causing OOMs
Using ComponentSupport, optimize import
Using component support
Deprecated resource store utils.

Only one method used in only one place, so moved it in.
Updated packaging mapper.
Deprecated smart wastebasket.
Removed MetadataManager inferface, as this made a mess here
Add OPTIONS handler method to PlexusResource

This will allow CORS headers (Access-Control-Allow-Origin) among other things in restful services.
Merge remote-tracking branch 'origin/master' into context-and-repo-cleanup

Conflicts:
	components/nexus-core/src/main/java/org/sonatype/nexus/proxy/repository/ProxyRepository.java
	components/nexus-core/src/main/java/org/sonatype/nexus/proxy/repository/Repository.java
	components/nexus-core/src/main/java/org/sonatype/nexus/scheduling/DefaultRepositoryTaskActivityDescriptor.java
	components/nexus-core/src/main/java/org/sonatype/nexus/scheduling/DefaultRepositoryTaskFilter.java
	components/nexus-core/src/main/java/org/sonatype/nexus/scheduling/RepositoryTaskActivityDescriptor.java
	components/nexus-core/src/main/java/org/sonatype/nexus/scheduling/RepositoryTaskFilter.java
	components/nexus-core/src/main/java/org/sonatype/nexus/scheduling/TaskActivityDescriptor.java
	components/nexus-core/src/main/java/org/sonatype/nexus/scheduling/TaskFilter.java
[NEXUS-6004] replace CompositeException usage with helper to attach suppressed exceptions
Squashed commit of the following:

commit 6765abea4e124ba6d27553e2cb1e13e2e2642cd2
Merge: 567e1d3 3675dd6
Author: Jason Dillon <jason@planet57.com>
Date:   Sat Nov 9 14:10:01 2013 -0800

    Merge branch 'nexus-2.7.x' into NEXUS-6004-composite-supressed-exceptions

commit 567e1d3c4d6c9558cae08564ae419a35af13d264
Author: Jason Dillon <jason@planet57.com>
Date:   Sat Nov 9 13:44:23 2013 -0800

    Update to goodies 1.7.4-SNAPSHOT
    Use Throwables2.composite() helper

commit 4de98801fa43ff18e660b19ca68aad22e6015552
Author: Jason Dillon <jason@planet57.com>
Date:   Fri Nov 8 15:03:01 2013 -0800

    [NEXUS-6004] replace CompositeException usage with helper to attach suppressed exceptions
REVIEW: terse logging for EOFException unless debug is enabled

Squashed commit of the following:

commit 3ad7123f7c8c236310ac71e0847b5734bb50c3ba
Author: Jason Dillon <jason@planet57.com>
Date:   Sat Nov 9 14:15:55 2013 -0800

    Use goodies 1.7.4-SNAPSHOT

commit 9985f9397bbcd2cb5550128364ce991bfcb90c41
Merge: e48d1ab 3675dd6
Author: Jason Dillon <jason@planet57.com>
Date:   Sat Nov 9 14:15:31 2013 -0800

    Merge branch 'nexus-2.7.x' into eofexception-terse-logging

commit e48d1ab9d5440244a1ee0128f7963099235e77a7
Author: Jason Dillon <jason@planet57.com>
Date:   Fri Nov 8 12:20:53 2013 -0800

    depend on goodies 1.8-SNAPSHOT to pick up Throwables2
    When not debug explain exception causal-chain tersely

commit f7a958220b64d36e4b4bdcc50139de9f8a6799f6
Author: Jason Dillon <jason@planet57.com>
Date:   Fri Nov 8 11:39:40 2013 -0800

    terse logging for IOException unless debug is enabled, trace above is too loud

commit 4df53e544586d2f56803641525abb8c10c1f153c
Author: Jason Dillon <jason@planet57.com>
Date:   Fri Nov 8 10:41:20 2013 -0800

    terse logging for EOFException unless debug is enabled
Merge pull request #242 from gnagy/master

Add OPTIONS handler method to PlexusResource
use  goodies 1.7.4
Merge pull request #222 from sonatype/context-and-repo-cleanup

[2.8] Changes stemming for weekend talk with JD
Merge remote-tracking branch 'origin/master' into NEXUS-6090-velocity

Conflicts:
	buildsupport/goodies/pom.xml