Added importer community module.

The importer modules were previously exclusively part of the OpenGeo Suite.
updating module names to include Importer prefix
updating sources to include copyright headers
Removing dependency on restlet json, using net.sf.json instead
removing hard dependencies on libs inheireted on geoserver main
removing preview link to geoexplorer
GEOS-5967: Provide default mapping instead of empty mapping in CSW
GEOS-5960 fixed test connection in LDAP Authentication Provider GUI
Merge pull request #295 from mbarto/geos_5960_ldap_test_connection

GEOS-5960 fixed test connection in LDAP Authentication Provider GUI
- Further clarifications for idExpression in app-schema.
Update app-schema-online-test guide for 3D Oracle tests with the SC4OUser parameter.
Merge pull request #292 from NielsCharlier/csw

GEOS-5967: Provide default mapping instead of empty mapping in CSW
Merge branch 'master' into importer

Conflicts:
	src/community/pom.xml
	src/web/app/pom.xml
Merge pull request #285 from jdeolive/importer

Added importer community module.
poms - make work with maven 3

remove versions unless needed (maven warnings) and shuffle some
deps to the parent
Fixed maven3 pom warnings.

- Declaring version for all plugins
- using project.build.outputDirectory rather than just build.outputDirectory
Merge pull request #297 from jdeolive/fix_pom_warnings

Fixed maven3 pom warnings.