Reapply r99735 "Change default --jobs value from 1 to 4."

It should be fine now that requirements with /@ works fine.

R=dpranke@chromium.org
BUG=
TEST=


Review URL: http://codereview.chromium.org/7782034

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@100162 0039d316-1c4b-4281-b951-d872f2087c98

gclient.py

@@ -1281,7 +1281,7 @@ def GenUsage(parser, command):
 def Parser():
   """Returns the default parser."""
   parser = optparse.OptionParser(version='%prog ' + __version__)
-  parser.add_option('-j', '--jobs', default=1, type='int',
+  parser.add_option('-j', '--jobs', default=4, type='int',
                     help='Specify how many SCM commands can run in parallel; '
                           'default=%default')
   parser.add_option('-v', '--verbose', action='count', default=0,