py3: make contrib/dumprevlog use absolute_import

contrib/dumprevlog

@@ -1,25 +1,31 b''
 #!/usr/bin/env python
 # Dump revlogs as raw data stream
 # $ find .hg/store/ -name "*.i" | xargs dumprevlog > repo.dump
 
+from __future__ import absolute_import
+
 import sys
-from mercurial import revlog, node, util
+from mercurial import (
+    node,
+    revlog,
+    util,
+)
 
 for fp in (sys.stdin, sys.stdout, sys.stderr):
     util.setbinary(fp)
 
 for f in sys.argv[1:]:
     binopen = lambda fn: open(fn, 'rb')
     r = revlog.revlog(binopen, f)
     print "file:", f
     for i in r:
         n = r.node(i)
         p = r.parents(n)
         d = r.revision(n)
         print "node:", node.hex(n)
         print "linkrev:", r.linkrev(i)
         print "parents:", node.hex(p[0]), node.hex(p[1])
         print "length:", len(d)
         print "-start-"
         print d
         print "-end-"