Merged from trunk 6634:6644

   Merged from trunk 6634:6644

   +------------------------------------------------------------------------+
   | 6634    | Fix broken dict.get logic.                                   |
   | zmedico |                                                              |
   |---------+--------------------------------------------------------------|
   | 6635    | Fix logic for USE_EXPAND variables that are incremental      |
   | zmedico | (there are none currently).                                  |
   |---------+--------------------------------------------------------------|
   | 6637    | In the WorldHandler class, add support for an onProgress     |
   | zmedico | callback that can be used notify the user of job progress.   |
   |         | This isn't really useful for WorldHandler since it completes |
   |         | quickly, but it will be useful for longer running tasks.     |
   |---------+--------------------------------------------------------------|
   | 6638    | Add a get_term_size() function that uses the curses module   |
   | zmedico | if available and otherwise falls back to parsing the output  |
   |         | of `stty size`.                                              |
   |---------+--------------------------------------------------------------|
   | 6639    | Add progress support to emaint (similar to wget's progress   |
   | zmedico | bar).                                                        |
   |---------+--------------------------------------------------------------|
   | 6640    | Add SIGWINCH support so that the progress bar is resized if  |
   | zmedico | the xterm is resized.                                        |
   |---------+--------------------------------------------------------------|
   | 6641    | Fix an UnboundLocalError when there's no tty.                |
   | zmedico |                                                              |
   |---------+--------------------------------------------------------------|
   | 6642    | Fix a typo.                                                  |
   | zmedico |                                                              |
   |---------+--------------------------------------------------------------|
   | 6643    | Add an emaint "binhost" target which does the time consuming |
   | zmedico | population of $PKGDIR/Packages that is necessary for a       |
   |         | binhost (MD5 makes it relatively slow). It reuses metadata   |
   |         | from the existing Packages file whenever possible.           |
   |---------+--------------------------------------------------------------|
   | 6644    | Make emaint prune stale entires from $PKGDIR/Packages.       |
   | zmedico |                                                              |
   +------------------------------------------------------------------------+

svn path=/main/branches/prefix/; revision=6646