[jaring] plugins.CopyButtons: disable button when no data selected.
[jaring] add copy icon.
[jaring] Merge js.SearchField to plugins.SearchField.
[jaring] jx.plugins.ImportButton: grid plugin to import file to database.
[jaring] jx.GridPaging: remove unneeded comments.
[jaring] jx.plugins.CopyButton: register plugin to Ext.
[jaring] lib.Jaring::dbPrepareInsert: change function to public.
[jaring] add icon for import.