CRM-12046 save campaign id in the petition signature

It needs to be applied as well to 4.2

patch by ken.

FYI: I had a problem with totten instructions:

$ git checkout upstream/master -b cool-footerfatal: git checkout: updating paths is incompatible with switching branches.
Did you intend to checkout 'upstream/master' which can not be resolved as commit?

So i did:

$ git pull upstream master
$ git push
$git checkout  master -b bugfix
instead and then went back on the totten track