wip
Use TrackRecord::Log to log messages in DataImport
Merge branch 'develop' of github.com:CartoDB/cartodb20 into feature/importer_log
Prefix redis key for DataImport logs
Optionally pass an expiration time to keys stored in Redis
Implement #exists? to check for keys in DataRepository backends
Optinally set a log expiration in TrackRecord
Merge branch 'develop' of github.com:CartoDB/cartodb20 into feature/importer_log
Add spec to ensure logger attribute in DataImport isn't overwritten