Bug Fix: Added missing Head Block functionality

- Added Head Block (metadata) functionality
- Consistency: updated test_client_deuce_blocks.py to use 'block_id' instead of 'blockid'
- Bug Fix: There is no content-type returned for heading a block, even from Storage
Update: Version for Package
Merge pull request #40 from BenjamenMeyer/bugfix_finds_by_valere_3

Bugfix finds by valere 3