chore(fixes): Unwrap yaml before converting and fix volume name variable

2 fixes:

- the first problem to resolve is that some volume names can have "-" in
the name. We now replace them by "_"
- the second problem is that k8s.io library truncates the lines and so
we cannot split the files by lines. We now "unwrap" the result.

TODO: globalize the `yaml.Marshal()` code to our own specific function

generator/volume.go

@@ -76,6 +76,8 @@ func (v *VolumeClaim) Yaml() ([]byte, error) {
 		return nil, err
 	}
 
+	out = UnWrapTPL(out)
+
 	// replace 1Gi to {{ .Values.serviceName.volume.size }}
 	out = []byte(
 		strings.Replace(