Added support for --max-changes=<count> to ease import debugging

Signed-off-by: Simon Hausmann <shausman@trolltech.com>
diff --git a/contrib/fast-import/git-p4 b/contrib/fast-import/git-p4
index 969c1fe..3d97ce1 100755
--- a/contrib/fast-import/git-p4
+++ b/contrib/fast-import/git-p4
@@ -499,7 +499,8 @@
                 optparse.make_option("--detect-labels", dest="detectLabels", action="store_true"),
                 optparse.make_option("--with-origin", dest="syncWithOrigin", action="store_true"),
                 optparse.make_option("--verbose", dest="verbose", action="store_true"),
-                optparse.make_option("--import-local", dest="importIntoRemotes", action="store_false")
+                optparse.make_option("--import-local", dest="importIntoRemotes", action="store_false"),
+                optparse.make_option("--max-changes", dest="maxChanges")
         ]
         self.description = """Imports from Perforce into a git repository.\n
     example:
@@ -521,6 +522,7 @@
         self.syncWithOrigin = False
         self.verbose = False
         self.importIntoRemotes = True
+        self.maxChanges = ""
 
     def p4File(self, depotPath):
         return os.popen("p4 print -q \"%s\"" % depotPath, "rb").read()
@@ -971,6 +973,9 @@
 
                 changes.reverse()
 
+                if len(self.maxChanges) > 0:
+                    changes = changes[0:min(int(self.maxChanges), len(changes))]
+
             if len(changes) == 0:
                 if not self.silent:
                     print "No changes to import!"