Support for SSL Redirect Annotation and > 80 char resource names

This release carries out:

• Support for SSL Redirect annotation.
• Fix for longer than 80 char resource names.
• Removed ingress prefix from the resource name and replaced it with a tag.

Introducing Health Probes support

This release introduces support for configuring Health Probes for Backend Pool (Pods) behind Application Gateway.
Probes will be configured based on settings provided in the below list in order:

1. Readiness Probe
2. Liveness Probe
3. Backend Prefix
4. Path in the Ingress
5. Default Probe

Please look up documentation for more information.

Introducing custom health probes.

Health probe on appgw backend will be generated based on fallback from the below list:

1. Readiness Probe
2. Liveness Probe
3. Backend Prefix
4. Path in the Ingress
5. Default Probe
   We will use Readiness Probe and Liveness Probe provided in the container spec of the deployment/pods served by the service in the ingress. Container will be picked by matching the service selector and port with the container Port.

Support for WAF SKU and hardening TLS

Release Notes:

• Adds support for WAF SKU with auto-scale.
• Disables HTTP listeners on ingress for which TLS spec is specified.

Updating the go SDK for AG in order to support WAF auto-scaling config.

Updating go packages to peg against the latest AG SDK (#114)

We weren't able to use the autoscale configuration with WAF v2 since the ingress controller was using an older version of the go SDK. Moving to the latest go SDK in order to enable these configuration.

Introduce backend prefix annotation.

To support backends that host endpoints different than the ones exposed in an ingress resource, we are introducing backend prefix annotations. This allows the ingress controller to setup a backend prefix HTTP setting for endpoints mentioned in an ingress resource with this annotation.

Read more about the usage of the backend prefix annotation here:
https://azure.github.io/application-gateway-kubernetes-ingress/docs/annotations.html#backend-path-prefix

Issues fixed:
#49

Introduce Backed prefix annotation

To support backends that host endpoints different than the ones exposed in an ingress resource, we are introducing backend prefix annotations. This allows the ingress controller to setup a backend prefix HTTP setting for endpoints mentioned in an ingress resource with this annotation.

Read more about the usage of the backend prefix annotation here:
https://azure.github.io/application-gateway-kubernetes-ingress/docs/annotations.html#backend-path-prefix

Fixes ingress controller behavior during service deletion

Release Notes:
#59 : The ingress controller no longer errors out when a service referenced in the Ingress resource is not present. Paths for which services have not yet been launched in k8s the ingress controller will still install the paths in the application gateway, but with empty backend pools.

Fixes ingress controller behavior during service deletion

Also fixes travis-ci deployment.

Fixes ingress controller issues with service deletion

Also, we want to test our docker container image push in the candidate release.