andyf's sandbox: Batch Entity Validate

Validates content entities.

Examples:
 drush batch-entity-validate --entity-type=node                    Validate all users            
 drush batch-entity-validate --entity-type=node --entity-type=user Validate all nodes and users  
 drush batch-entity-validate --all                                 Validate all content entities 

Options:
 --entity-type=ENTITY-TYPE Entity type to validate                                                                                                                    
 --batch-size[=BATCH-SIZE] Number of entities to load in one go [default: 50]                                                                                         
 --format[=FORMAT]         Format the result data. Available formats: csv,json,list,null,php,print-r,sections,string,table,tsv,var_dump,var_export,xml,yaml [default: 
                           table]                                                                                                                                     
 --all                     Validate all entities                                                                                                                      
 --fields=FIELDS           Available fields: Entity Type (entity_type_id), Entity ID (entity_id), Path (path), Message (message), Code (code), Link (link) [default:  
                           entity_type_id entity_id path message]                                                                                                     
 --field=FIELD             Select just one field, and force format to *string*.                                                                                       
 --filter[=FILTER]         Filter output based on provided expression