Add support for skipTlsVerify provisioning parameter #311
Description
Most native Grafana plugins that use HTTPS calls support the skipTlsVerify: true parameter in the datasource provisioning file.
It would be useful to support that in this plugin as well, for local installations using self-signed or internal PKI certificates.
See the provisioning example at https://grafana.com/docs/grafana/latest/administration/provisioning/#data-sources .