Added CapAdd and CapDrop host config options from Docker 1.2
Add David Huie as an author
Merge pull request #145 from DavidHuie/cap

CapAdd and CapDrop host config options from Docker 1.2
Update tags for marshal/unmarshalling

Update tags for all structs that a user may want to marshal:
- add yaml tags everywhere
- update case to match Docker's format

Rename MaxRetry -> MaximumRetryCount for consistency with Docker.