Add a function to export data to file

[outsmain]

• Support file format are excel (.xlsx) / tab delimited (.txt)
• Export all rows (every sub pages) in current report type
• Default file name is "authrep-user.(xlsx/txt)" or "authrep-device.(xlsx/txt)" depends on report type
• Export data use the same format as HTML table
• Add a jQuery UI's split button "Export data" below data table:
• When user click a link on each file type, open a new non-modal (not block other element on a page) size 250x140 px at position bottom right of the page, display a message "Export data..." until data are ready to export then open the browser's save dialog