Warn about tags when project is moved

[Gibbon1]

I've run into an annoyance when copying a project to a different directory which is the *.tags file contains hard paths to the previous location. Going to the definition or implementation of a symbol opens the file on the old location. That can be a bit confusing if you don't notice or know to watch for it.

Would be nice if the .tags database remembered the where it was created and bitch a little if the location changes.

Bitching meaning ask if you want to re-parse the project when you open it and the tags database has moved.

[eranif]

Sounds like a good idea.
Can you please submit this to GitHub?

Thanks!