Fix typo: Uncommment => uncomment

Pointed out by Dan Winship
edit_template: assume commit messages are valid utf8

When reading git commit message to be used as editable templates,
assume they use the utf8 encoding before invoking edit_template().

In any case, while git does not enforce any encoding it will
complain if a commit message is not valid utf-8.

https://bugzilla.gnome.org/show_bug.cgi?id=684578
push: Add --no-reupload to avoid reuploading unchaged patches

By default `git bz push` re-uploads all the pushed commits which may be
annoing if these are just what has been approved during review,

By using `git bz push --no-reupload --fix $BUG origin master` it is now
possible to avoid all the extra noise when closing bugs.