- methods in PhotoDB that return something now return null if an exception
  is thrown; those that don't throw that exception itself
- methods that require a connection now throw an IllegalStateException if
  there is no connection
- added ability to change temp/cache directory
- fixed bug where JScrollPanes were overlapping after >1 connects
- updated documentation
minor tweaks
- can now select/delete multiple photos in PhotoPanel
- rearranged methods in PhotoPanel somewhat
- fixed bug where PhotoDB used partly-cached files
perhaps the final jar
updated to reflect changes in PhotoDB
more general use of caching folder; fixed file deletion bugs and allow StreamWriter to be stopped from a different thread
another 'final' version'
updated README with 1/2 features