Grouped commit for Jenkins authentication plugin:

Replaced Spring classes with Acegi classes; cleaned up .classpath

Using managed dependencies; master pom now building plugin

Updated Jenkins web project to include our first custom Jenkins plugin

Renamed package from hudson to jenkins

Change-Id: I509eb67736d8336276e1da2e911aa8f6e12132c8
Reviewed-on: https://q.tasktop.com/alm/s/c2c-oss/gerrit/75
Tested-by: Hudson
Reviewed-by: Myles Feichtinger <myles.feichtinger@tasktop.com>
Reviewed-by: Michael Nelson <michael.nelson@tasktop.com>
Updated modules selected in base pom. 'hudson' profile (active by
default) adds Hudson modules; 'jenkins' profile adds Jenkins modules.