git-svn: extract reusable code into utility functions
Extacted canonicalize_path() in the main package.
Created new Git::SVN::Util package with an md5sum() function. A
new package was created so that Digest::MD5 did not have to be
loaded in the main package. Replaced code in the SVN::Git::Editor
and SVN::Git::Fetcher packages with calls to md5sum().
Extracted the format_svn_date(), parse_git_date() and
set_local_timezone() functions within the Git::SVN::Log package.
Signed-off-by: David D. Kilzer <ddkilzer@kilzer.net>
Acked-by: Eric Wong <normalperson@yhbt.net>