+ - ensure that architectures are not added multiple times
+ * cmdline/apt-mark.cc:
+ - detect if dpkg has multiarch support before calling --set-selections
+ - correctly ignore already (un)hold packages
+ * apt-pkg/cachefile.cc:
+ - clean up lost atomic cachefiles with 'clean' (Closes: #650513)
+ * apt-pkg/indexrecords.cc:
+ - do not create empty Entries as a sideeffect of Lookup()