cdm/src/main/java/ucar/nc2/AttributeContainerHelper.java
@Override
  public boolean removeAttributeIgnoreCase(String attName) {
    Attribute att = findAttributeIgnoreCase(attName);
    return att != null && atts.remove(att);
  }
@Override
  public boolean removeAttributeIgnoreCase(String attName) {
    Attribute att = findAttributeIgnoreCase(attName);
    return att != null && atts.remove(att);
  }
Remove an Attribute by name, ignoring case

@param attName if exists, remove this attribute
@return true if was found and removed