Import CA certificates

[arbulu89]

Update: Apparently, the initial certificates we created for our demo IDP, they were created wrong, and that's why we were required to upload them to the machine. This means, that the requirement of uploading custom CA certs shouldn't be that important (actually, It would become a small corner case), so we can postpone this by now

Add option to import CA certificates to the cluster.
When SSO options are used and the IPD is hosted using TLS, the client (trento web in this case) must have the CA certificate installed in the system. This in helm is not a default scenario in many cases.

In order to have the option to import the CA certificates, I have added this new variable caStoreConfigmap that we can use for this purpose.
The usage would be like:

1. Download the server CA (the whole chain) to your local machine as a .pem file. Put this certificate in a new folder
2. Create a config map so the content can be uploaded to helm. For that: kubectl create configmap ca-pemstore --from-file=/folder_with_ca/. The name ca-pemstore can be any other string
3. Run helm as usual adding this new variable: helm ... --set trento-web.caStoreConfigmap=ca-pemstore

With this, all the content in the /folder_with_ca/ is imported in the pod and trento web can use them.