ResultsWindow: the results table now displays file sizes (in bytes or
kilobytes) on the right-most column.
ResultsWindow: changed how the results metadata is displayed, added a
status bar, added the ability to copy the path of the file entry at
selected row to the clipboard when double-clicked.

MainWindow: began implementing results history viewing.

ContentIndex: removed a debug console output call while building the
index.

DFScan: removed unnecessary code.
MainWindow: implemented the report/results history browser, added
functionality to open the selected report in a ResultsWindow when a the
report's table entry is double-clicked.
MainWindow: continued implementing the results report history viewer.

ResultsWindow: implemented the 'select all' and 'select none' button
behaviors.
Merge branch 'redesign_results_window'