Update redis schema to include URL and TLS (#631)

* update redis schema

* addressing comments

docs/content/reference/resource-schema/link-schema/cache/redis/index.md

@@ -49,6 +49,7 @@ The `redislabs.com/Redis` link is a [portable link]({{< ref links-resources >}})
 | [resources](#resources)  | n | An array of IDs of the underlying resources for the link. | [See below](#resources)
 | username | n | The username for Redis cache. | `myusername`
 | [secrets](#secrets) | n | Secrets used when building the link from values. | [See below](#secrets)
+| tls | n | Indicates if the Redis cache is configured with SSL connections. If the `port` value is set to 6380 this defaults to `true`. Otherwise it is defaulted to false. If your Redis cache offers SSL connections on ports other than 6380, explicitly set this value to `true` to override the default behavior. | `true`
 
 #### Recipe
 
@@ -69,6 +70,7 @@ The `redislabs.com/Redis` link is a [portable link]({{< ref links-resources >}})
 |----------|:--------:|-------------|------------|
 | connectionString | n | The connection string for the Redis cache. Write only. | `https://mycache.redis.cache.windows.net,password=*****,....`
 | password | n | The password for the Redis cache. Write only. | `mypassword`
+| url | n | The connection URL for the Redis cache. Set automatically based on the values provided for `host`, `port`, `username`, and `password`. Can be explicitly set to override default behavior. Write only. | `redis://username:password@localhost:6380/0?ssl=true` |
 
 ### Methods