Runs s3 storagedriver tests against all regions (excluding gov)
Uses random paths with slashes for storagedriver tests, adds edge cases

This replaces only using flat filenames, to better test nested file
behaviors.
Fixed inmemory/mfs.go and filesystem/driver.go after finding bugs with
the new tests and test behavior.
Implement Tags method on ManifestService
Implement tags HTTP API handler
Move manifest store errors to where they happen
Remove errant log message
Add error code for unknown repository
Test Tags HTTP API methods during manifest upload
Fixes normalization of inmemory file paths

A normalized path always begins with "/" and never has a trailing slash
unless it is the root directory.
Makes circle.yml run tests with the "-test.short" flag

This is due to longer tests which require more storage/memory than is
granted to us by the circle test runner vms.
Merge pull request #832 from BrianBland/ng-storagedriver-tests

Updates storagedriver tests to better test directory trees
Merge pull request #834 from stevvooe/next-generation

Implement tags HTTP API handler
Update LICENSE
Adds another error test case for reading nonexistent files
Improves storagedriver tests for Move command semantics

Ensures that Move will properly overwrite the file at the destination
location.
Also checks that Move of a nonexistent source file will NOT delete the
file at the destination.
Fixes storagedriver Stat test

Checks Stat on the directory before creating the file to make sure that
it does not exist
Properly cleans up after the test.
Improves storagedriver concurrency testing

Creates trees instead of flat files for TestConcurrentFileStreams

Adds TestConcurrentStreamReads, which writes a large file (smaller in
Short mode), and then ensures that several concurrent readers properly
read their portions of the file with random offsets
Attempts to fix go vet for circle
Merge pull request #837 from BrianBland/ng-storagedriver-tests

Various storagedriver test additions/improvements
Disabling go vet until we get bug fixed