updates code to be compatible with:
- github.com/minio/mc v0.0.0-20200415193718-68b638f2f96c
- github.com/minio/minio v0.0.0-20200415191640-bde0f444dbab
Note: admin_config api is patched temporarily now to
return the target configuration as a raw string due to the
changes done on minio.
addPolicy endpoint will read policies as json string, this to allow
s3 iam policy compatibility (uppercase in json attributes) and to be
consistent with other mcs apis, once https://github.com/minio/minio/pull/9181
is merged we can return a type struct{}
fix policies test to new refactor
goimports
more golint fixes
