Getting unused import of "scala.conversion.JavaConverters._" for enum in generated .scala files

[skvithalani]

Thanks for the release of 0.6.7. The warning I reported at #358

Warning:(8, 40) Unused import
import scala.collection.JavaConverters._

is fixed for messages but not for enum types. Here is a sample of enum proto file that we are using in our project

syntax = "proto3";

package csw_protobuf;

enum PbUnits {
    //default unit
    NoUnits = 0;

    // SI units
    angstrom    = 1;
    arcmin      = 2;
    arcsec      = 3;
 }