Support Multiple Vault Secret Paths (#6)

Add a check to determine if token is renewable before trying to renew. (#5)

Update build instructions

Add --generate-config as a mechanism to get the Vault config.

Fix a bug that kept trying to renew leases that could not be renewed.

Remove govendor references in README

Merge pull request #3 from funnylookinhat/auto-renew-token

Use a basic string concatenation for the URL.

Add periodic token renewal.

Merge pull request #1 from funnylookinhat/dahv-review

Cleanup error reporting in main.go

Clean up errors.

Refactor to use a type for the Vault response, address comments.

Comments on concurrency model with RunWithEnvVar

Error checking and possible simplification on secrets fetch