Option to pass --localtime to git

[ToeBee]

By default, the git svn fetch command puts all commit times in UTC. If you import the resulting repository to GitHub then all the commit graphs are based on UTC. This means that my repositories look most active late at night which is not very useful.

Adding --localtime to the git svn fetch command on line 183 of migration.rb causes it to record the time with the local time zone indicated. This causes GitHub detect your time zone and adjust the graphs accordingly.

Output from git log before and after for the most recent commit:
Date: Tue Jun 25 15:55:18 2013 +0000
Date: Tue Jun 25 10:55:18 2013 -0500