Feature: support multiple yamlFile values overrides

[gpettey]

Helm supports defining multiple files to read values from. This plugin should support the same. Currently only the last <yamlFile> entry from the pom is read.

[Kirill Nazarov]

While PR is in review, you can pass multiple yaml values files via comma separated list :-)
E.g.:

<yamlFile>path/to/values-1.yaml,path/to/values-2</yamlFiles>

[Kirill Nazarov]

PR merged, new version released. Can you please check based on README.md

[Kirill Nazarov]

@sschnabe should be closed.