Remove the branch copy heuristic

The FreeBSD project has a different approach to branches than the
standard SVN or GIT models of how branches should work. An MFC from
head/ to stable/8 is a cherry-pick in git and should never result in a
merge commit.

Sadly, this means that "IFCs" from head/ to project/foo also no longer
are merge commits, though they really are ...

Reported by: Ryan Stone <rysto32@gmail.com>

Author: uqs

src/svn.cpp

@@ -779,18 +779,6 @@ int SvnRevision::exportInternal(const char *key, const svn_fs_path_change_t *cha
         transactions.insert(repository + branch, txn);
     }
 
-    //
-    // If this path was copied from elsewhere, use it to infer _some_
-    // merge points.  This heuristic is fairly useful for tracking
-    // changes across directory re-organizations and wholesale branch
-    // imports.
-    //
-    if (path_from != NULL && prevrepository == repository && prevbranch != branch) {
-        if(ruledebug)
-            qDebug() << "copy from branch" << prevbranch << "to branch" << branch << "@rev" << rev_from;
-        txn->noteCopyFromBranch (prevbranch, rev_from);
-    }
-
     if (change->change_kind == svn_fs_path_change_replace && path_from == NULL) {
         if(ruledebug)
             qDebug() << "replaced with empty path (" << branch << path << ")";