Search in current directory or marked files

Hi!
I made  a little command for search in current folder or marked files.
I’m sorry, but actually code need to be

```python
where = ', '.join(join(self.path, p) for p in self.get_marked()) or self.path or ''
```

Because `get_marked` returns filenames, while we need full paths, especially for folders.  That is do not trust anybody who throws at you some code :smile: 

Anyway, I need to add description to readme, so I’ll merge by hand, don’t change it. Thanks again for usefull stuff.