Please support rsync filter files

[ebmi]

Backintime is very nice, but I would like to customize further the include/exclude filtering passed to rsync. In my case I would only like to backup subfolders that begin with the character '_' in a given folder. This could be accomplished if include patterns were supported, but it would be easier to include an expert rsync filter file option. For example, a simple filter rule of '-! /_**' would suffice to accomplish my goal.

I noticed that this bug was filed and apparently fixed with bug #362057 in 2009, but I'm not sure what happened to the fix. I am using version 1.0.6 and the expert option mentioned in the above bug report is not in the gui, nor is it in the snapshots.py file.

Thanks for great software!