annother feature request: recording conversion metadata

[denial]

I've been doing some bulk conversions and imports and thought of this.

I would be nice to mark files added or imported as "Original" and warn about possible deletion or overwrite. And then record conversion settings, calibre version, and source file for subsequent conversions.

So if I import a PDF and convert it to LIT, then MOBI then EPUB. And a new version of Calibre comes out with a bugfix for creating MOBI files I can re-convert those MOBI files from the original PDF not from the EPUB that may have been based on the MOBI.

Also if I look at a title that has MOBI, LIT, TXT and RTF, and both "RTF and LIT" are marked as "Original" I know I can delete the RTF and TXT files without loosing any information (since LIT files seem to hold more book info than RTF) and still have formats for my devices.

Clear as mud?
-dan