Merge pull request #22 from namn/add-client-go

Add client-go project.
Add admin login restriction to the mapreduce urls
Remove dead code
Delete unused file
Remove mockcoverage and sampledata

Users now have to run a map reduce pipeline over real data
Cleanup logs and comments
Add deployment info
More small, mostly comment, cleanups
Use non-github httr package
client-go: Support OAuth2 and ReadsetsSearch

The script now performs near full discovery of readsets and reads. The
dataset is still hardcoded to 1000 Genomes dataset. When
``datasets/list`` is implemented, we can do full discovery.