move thumbnail generation dokuwiki.org #51 #50

resizing external images depends on a large fetchsize config. Since we
cannot assume that everybody has this and loading huge images as
thumbnails is slow as hell this moves thumbnail generation to server in
splitbrain/dokuwiki-plugin-pluginrepo@2890faf7aafeded7d818b2091bbad53fe4fbd648
Removed last piece of action checkboxes
Removed last pieces of quick search
Removed last pieces of special searchlink styling
Removed dead code, version compatibility information. Closes #25
Implemented disable all action, moved button code to plugin tab
Renamed function for clearer code
Removed last bits of table layout related code
Added some explanation to popularity, closes #52
Some lang.php cleanup
Don't delete repo cache if server not found, closes #55