Fix #533, add a reader for lease values (#529) and an acceptance test for mysql to prove it works

[ctennis]

No description provided.

[ctennis]

mysql acceptance test:

=== RUN TestBackend_basic
2015/08/13 15:31:20 [INFO] core: security barrier initialized (shares: 1, threshold 1)
2015/08/13 15:31:20 [INFO] core: post-unseal setup starting
2015/08/13 15:31:20 [INFO] core: post-unseal setup complete
2015/08/13 15:31:20 [INFO] core: root token generated
2015/08/13 15:31:20 [INFO] core: pre-seal teardown starting
2015/08/13 15:31:20 [INFO] rollback: starting rollback manager
2015/08/13 15:31:20 [INFO] rollback: stopping rollback manager
2015/08/13 15:31:20 [INFO] core: pre-seal teardown complete
2015/08/13 15:31:20 [INFO] core: vault is unsealed
2015/08/13 15:31:20 [INFO] core: post-unseal setup starting
2015/08/13 15:31:20 [INFO] core: post-unseal setup complete
2015/08/13 15:31:20 [INFO] rollback: starting rollback manager
2015/08/13 15:31:20 [INFO] core: mounted 'mnt/' type: test
2015/08/13 15:31:20 [WARN] Executing test step 1
2015/08/13 15:31:20 [WARN] Executing test step 2
2015/08/13 15:31:20 [WARN] Executing test step 3
2015/08/13 15:31:21 [WARN] Generated credentials: {root-027c6ade-b3 d6ddbc73-e293-f0d2-1403-15e34532e746}
2015/08/13 15:31:21 [WARN] Revoking secret: *logical.Request{Operation:"write", Path:"sys/revoke/mnt/creds/web/10b689ae-53a3-856a-abce-923d6c706216", Data:map[string]interface {}(nil), Storage:logical.Storage(nil), Secret:<nil>, Auth:<nil>, Connection:(*logical.Connection)(nil), ClientToken:"", DisplayName:"", MountPoint:""}
2015/08/13 15:31:21 [WARN] Requesting RollbackOperation
--- PASS: TestBackend_basic (1.42s)
=== RUN TestBackend_roleCrud
2015/08/13 15:31:21 [INFO] core: security barrier initialized (shares: 1, threshold 1)
2015/08/13 15:31:21 [INFO] core: post-unseal setup starting
2015/08/13 15:31:21 [INFO] core: post-unseal setup complete
2015/08/13 15:31:21 [INFO] core: root token generated
2015/08/13 15:31:21 [INFO] core: pre-seal teardown starting
2015/08/13 15:31:21 [INFO] rollback: starting rollback manager
2015/08/13 15:31:21 [INFO] rollback: stopping rollback manager
2015/08/13 15:31:21 [INFO] core: pre-seal teardown complete
2015/08/13 15:31:21 [INFO] core: vault is unsealed
2015/08/13 15:31:21 [INFO] core: post-unseal setup starting
2015/08/13 15:31:21 [INFO] core: post-unseal setup complete
2015/08/13 15:31:21 [INFO] rollback: starting rollback manager
2015/08/13 15:31:21 [INFO] core: mounted 'mnt/' type: test
2015/08/13 15:31:21 [WARN] Executing test step 1
2015/08/13 15:31:21 [WARN] Executing test step 2
2015/08/13 15:31:21 [WARN] Executing test step 3
2015/08/13 15:31:21 [WARN] Executing test step 4
2015/08/13 15:31:21 [WARN] Executing test step 5
2015/08/13 15:31:21 [WARN] Requesting RollbackOperation
--- PASS: TestBackend_roleCrud (0.36s)
=== RUN TestBackend_leaseWriteRead
2015/08/13 15:31:21 [INFO] core: security barrier initialized (shares: 1, threshold 1)
2015/08/13 15:31:21 [INFO] core: post-unseal setup starting
2015/08/13 15:31:21 [INFO] core: post-unseal setup complete
2015/08/13 15:31:21 [INFO] core: root token generated
2015/08/13 15:31:21 [INFO] core: pre-seal teardown starting
2015/08/13 15:31:21 [INFO] rollback: starting rollback manager
2015/08/13 15:31:21 [INFO] rollback: stopping rollback manager
2015/08/13 15:31:21 [INFO] core: pre-seal teardown complete
2015/08/13 15:31:21 [INFO] core: vault is unsealed
2015/08/13 15:31:21 [INFO] core: post-unseal setup starting
2015/08/13 15:31:21 [INFO] core: post-unseal setup complete
2015/08/13 15:31:21 [INFO] rollback: starting rollback manager
2015/08/13 15:31:21 [INFO] core: mounted 'mnt/' type: test
2015/08/13 15:31:21 [WARN] Executing test step 1
2015/08/13 15:31:21 [WARN] Executing test step 2
2015/08/13 15:31:21 [WARN] Executing test step 3
2015/08/13 15:31:21 [WARN] Requesting RollbackOperation
--- PASS: TestBackend_leaseWriteRead (0.15s)
PASS
ok      github.com/hashicorp/vault/builtin/logical/mysql    2.030s

[armon]

Thanks!