Use Digest::SHA instead of deprecated Digest::SHA1
Fix call-time pass-by-reference in new.php.

call_user_func can't be used as it never passes by reference,
so switch to using variable functions.
Use Digest::SHA instead of deprecated Digest::SHA1
Fix call-time pass-by-reference in new.php.

call_user_func can't be used as it never passes by reference,
so switch to using variable functions.
Merge branch 'wheezy-changes' of ssh://git.mysociety.org/data/git/public/petitions into wheezy-changes
update commonlib to latest to remove references to obsolete Digest::SHA1 module
Merge remote-tracking branch 'origin/wheezy-changes'