Fixed bug: call signature for add_product_codes() does not match call structure

Fixes TOOLS-106
Fixed bug: euca2ools.commands.euca.bundlevol gets dict of block_device_mapping from boto, and euca2ools.bundler.generate_manifest expects a list. fixed bundler to expect a dict, and euca2ools.commands.euca.bundleimage to also send one

Fixes TOOLS-107
Check for metadata that are missing altogether

Fixes the second stack trace in TOOLS-82
Update RNG bug URL
Version bump (2.0.3)