[Snails] Wrap "Copy message" into a QToolButton.
[Snails] Enable/disable message actions.
[Snails] Refactored folders getting into GetActualFolders().
[Snails] Check for empty folders path.
[Snails] Don't show current folder in Copy menu.
[Util] Derive CategorySelector from QDialog.
[Util] Removed useless API prefixes.
[Util] CategorySelector::SetButtonMode.
[Aggregator] Hide buttons in category selector.
[Interfaces] Bump API level.
[Util] GetSelections() now const.
[Util] Slight style fix.
[Util] Tags sorting in CategorySelector now optional.
[Util] CategorySelector::GetSelectedIndexes().
[Util] CategorySelector is a Dialog window now.
[Snails] Support copying to multiple folders.