Add auto resizable input dialog class
Use AutoExpandableDialog instead of QInputDialog wherever possible
Move textBox geometry updates into showEvent:

1. Makes QFontMetrics more accurate (~50%) for custom DPI systems
2. Makes it possible to have fixed dialog size yet again (like in old dialog box) and still allow to autoexpand the textBox
Try to center AutoExpandableDialog on the same screen as main window

If main window is unavailable use the screen, where the mouse cursor is.
Show delete action when multiple feeds are selected
Merge pull request #786 from Gelmir/inputDlg_autoexpand

Resize input dialogs to fit contents
Merge pull request #794 from Gelmir/rss_feed_del_multi

Show delete action when multiple feeds are selected
Load magnet metadata inside AddNewTorrentDialog
Add progress indicator for metadata retrieval