[PATCH V2] forget: add --dry-run mode

[Matt Harbison]

On Tue, 13 Mar 2018 17:30:55 -0400, sushil khanchi  
<sushilkhanchi97 at gmail.com> wrote:

> Shall I remove --dry-run from context layer now?

It looks like cmdutil.add() and scmutil.addremove() don't pass it along to  
wctx either, so I guess it's OK to drop for consistency.

But the fact that it doesn't seems like a bug- wctx.add() prints out  
various warnings about portable file names, sizes, etc.  I'd think that  
the whole point of a dry run is to test against that.  Maybe the solution  
to that is to have a mock wctx somehow that simply doesn't flush dirstate  
to disk?