2761 new role "content editor" and associated permissions

#2761

#### Instructions

Run `drush fr -y os os_biocv os_books os_blog os_classes os_events os_faq os_image_gallery os_links os_news os_pages os_presentations os_profiles os_publications os_reader os_software`

#### Changes

* Adds new role "content editor"
* Grants all group content node-type permissions to the new role
* EXCEPT "Delete any" (only "administrator" role has that ability)