Added utility scripts to dump/load the contents of DynamoDB tables.
Added dynamodb_dump/dynamodb_load to the list of scripts in setup.py.
Refactored dynamodb_dump/dynamodb_load into their own functions rather than dumping everything in main() functions.
Using errno.EEXIST rather than a literal 17 -- more compatibility.
Merge branch 'master' of git://github.com/maxnoel/boto into maxnoel-master