Adds .find and .all Plugin class methods.
Adds plugin id attribute.
Moves plugin list to its own administration menu item.
Changes version naming rule (#2162).
Translation updates (#2189, #2193)
Polish update, #2188
Translation updates (#2168, #2172, #2176, #2178)
Missed %s in label, thank Martin Bächtold for reporting (#2186)
Fixes #2170: user display format in application settings broken by r2010.
Fixes #2171: issue pdf export broken by r2006.
