apachesolr 6.x-3.0-beta2

#1679346: Service Class is badly defined in 6.x-3.x by Nick_vh: Fixed Service Class is badly defined in 6.x-3.x.
#1673086: Add drush commands to get, set, del environment variables by pwolanin: Add drush commands to get, set, del environment variables.
#1672738: Allow a dynamic apachesolr_process_results function by Nick_vh: Added Allow a dynamic apachesolr_process_results() function.
#1670834: Bundle specific overrides do not work as expected in drupal 6 by killua99, Nick_vh: Fixed Bundle specific overrides do not work as expected in drupal 6.
#1473722: Bundle specific overrides by levialliance: Added Bundle specific overrides.
#1408844: As a site builder I want to override the environment settings in settings.php by Nick_vh, jrbeeman: Added As a site builder I want to override the environment settings in settings.php.
#1668202: wrong redirect on admin/settings/apachesolr by killua99: Fixed wrong redirect on admin/settings/apachesolr.
#1665790: Nodes not indexed, Taxonomy needs to be set to be a multiple by snowfox: Fixed Nodes not indexed, Taxonomy needs to be set to be a multiple.
#1402748: Check in apachesolr_do_query if the static of the query with that name already exists, and if so return it by Nick_vh, killua99: Fixed Check in apachesolr_do_query() if the static of the query with that name already exists, and if so return it.
#1661004: warning: table <db>.taxonomy_index doesn't exist by killua99: Fixed warning: table .taxonomy_index() doesn't exist.
#1518108: Devel interface for inspecting solr documents by killua99, grendzy: Added Devel interface for inspecting solr documents.
#1658252: Sync rc2 configs by pwolanin: Sync rc2 configs.