DOC: introduction to users extensions
FIX: no view defined in a type
FIX: reopen tab view with source data
ENH: support store of sources
ENH: support for sources store, load, and free data
WIP: working on csv type
FIX: detach with selected param & check op. status
ENH: added modul with operation for csv files
ENH: loader supports filtering over all types
ENH: support arguments with callback in events
ENH: info about filtered sources; correct selecting parameters
FIX: correct run method in testaction
FIX: detach sources