title: UgilfyJS (version 2) -- how to get it to not drop unused
body: <p>Uglify drops variables it (wrongly) considers unused. It also warns about functions that it (wrongly) thinks are not referenced, but I have not looked yet to see if it actually drops them. It just doesn't see the whole universe at once -- none of these things it has identified as unused or unreferenced are unused or unreferenced. What CLI option will make it keep everything. My current CLI option list is:
      --compress sequences,drop_debugger,conditionals,comparisons,evaluate,booleans,loops,hoist_funs,if_return,join_vars,cascade,warnings 
      --lint 
      --mangle 
      --screw-ie8 
      --source-map $&lt;.map 
      --verbose 
      -- peramble ... copyright ...</p>