Fix name for a termporary array

The pkglist2 name was too cryptic to show why it's really there. Added a
few comments about it too.
Fix misspelling (canceled -> cancelled)

Both spellings are valid, but the one with the two 'l's is more natural.
Make search dialog buttons activatable

The search dialogs buttons ("clear search" and "search") were not
activatable anymore. This was probably due to an update in gtk/pygtk and
they needed to be explicitly made activatable now.
Fix double listings when a package failed to build

Only run refresh_pkglist when a package has been built and installed
succesfully. When a package build failed (or was cancelled)
refresh_pkglist was called twice, once directly and once through
on_menuitem_unmarkall_activate, resulting in double listings of
packages. This only showed when a string was entered in the package
search box.
Update translations from transifex

Update da, it, nl, pt_PT, ru and uk translations.
Revert "Fix misspelling (canceled -> cancelled)"

This reverts commit 2a57d561412a7bbd27edc940ffbc38a459a9a4f1.
Bugger that. It would change all translations too.