Bugfix finds by valere 6

- Shell should return 0 on success, 1 on errors
- StorageBlocks did not properly deserialize due to error with the for loop
- Added the add() convenience to StorageBlocks
- Added list files **new to PR as of ** https://github.com/BenjamenMeyer/deuce-client/commit/6557739c84f0004a9dd8847403276a75c2e76ce4
- Added delete blocks from command-line **new to PR as of ** https://github.com/BenjamenMeyer/deuce-client/commit/6557739c84f0004a9dd8847403276a75c2e76ce4