allow to reindex specific search_type
added rake task to reindex specific search_type
refactored serializers - added acts_as_event fields
mapping acts_as_event fields for news
mapping acts_as_event fields for changesets
mapping acts_as_event fields for documents
mapping acts_as_event fields for issues
mapping acts_as_event fields for messages
mapping acts_as_event fields for news
mapping acts_as_event fields for projects
removed includes from project searching scope
mapping acts_as_event fields for wiki_pages