Allow grep-root specification

[artagnon]

Often, we need to grep while working with files from multiple projects, or need to narrow grep within a subfolder of the current project. A prompt for directory name at the beginning of the grep would suffice.

[geksilla]

Hi, @artagnon. I'm gonna to add support for multiple projects but don't know when I can start it :crying_cat_face: For now you can use file filter mode to narrow grep output. To do that you need to hit Ctrl f when grep dialog opened and start typing directory/filename.