[PATCH] merge: show helpful message on file with directory name conflicts (issue29)

[Prasoon Shukla]

I apologize for the late reply. Been busy.

@Augie
1. To fix, user needs to rename the file/directory at either end. Or,
the conflicting file/directory can be deleted at either end.
2. In a nutshell, this error occurs whenever a file (directory)
collides with directory (file) of same name - tracked or not. This is
a filesystem error that occurs while trying to write the new
file/directory that is fetched. So, this will occur regardless of
whether the file is tracked or even if it is hgignored.
3. Well, mpm suggested this kind of message on the bugtracker, so I
went ahead with it. (http://bz.selenic.com/show_bug.cgi?id=29#c8)
I am open to suggestion as to how the message should look like.

@Adrian

Oh, okay. I am just getting started with hg so I don't really much of
an idea about this kind of thing. I suppose then, I can catch these
exceptions before the control goes to the vfs object?