* Add useragent package
This helper provides a consistent user-agent header for Vault, taking into account different versions.
* Add user-agent headers to spanner and gcs
This PR adds a new Storage Backend for Triton's Object Storage - Manta
```
make testacc TEST=./physical/manta
==> Checking that code complies with gofmt requirements...
==> Checking that build is using go version >= 1.9.1...
go generate
VAULT_ACC=1 go test -tags='vault' ./physical/manta -v -timeout 45m
=== RUN TestMantaBackend
--- PASS: TestMantaBackend (61.18s)
PASS
ok github.com/hashicorp/vault/physical/manta 61.210s
```
Manta behaves differently to how S3 works - it has no such concepts of Buckets - it is merely a filesystem style object store
Therefore, we have chosen the approach of when writing a secret `foo` it will actually map (on disk) as foo/.vault_value
The reason for this is because if we write the secret `foo/bar` and then try and Delete a key using the name `foo` then Manta
will complain that the folder is not empty because `foo/bar` exists. Therefore, `foo/bar` is written as `foo/bar/.vault_value`
The value of the key is *always* written to a directory tree of the name and put in a `.vault_value` file.
The original reason for the split was physical's dependencies, but those
haven't been onerous for a long time. Meanwhile it's a totally separate
implementation so we could be getting faulty results from tests. Get rid
of it and use the unified physical/inmem.
This change makes these errors transient instead of permanent:
[ERROR] core: failed to acquire lock: error=etcdserver: requested lease not found
After this change, there can still be one of these errors when a
standby vault that lost its lease tries to become leader, but on the
next lock acquisition attempt a new session will be created. With this
new session, the standby will be able to become the leader.
* Fix cassandra tests, explicitly set cluster port if provided
* Update cassandra.yml test-fixture
* Add port as part of the config option, fix tests
* Remove hostport splitting in cassandraConnectionProducer.createSession
* Include port in API docs
