Clarify %YEARS% in copyright templates, located in make/templates.

A suggestion was made as part of JDK-8015525 review

On 5/28/2013 8:50 PM, David Holmes wrote:
> On 29/05/2013 1:33 PM, Mike Duigou wrote:
>>
>> I have a partial solution and also the explanation for the missing commas in the lambda test files:
>>
>> The templates in make/templates don't include a comma after the %YEARS% variable. Can we add one to the templates? These templates are what I have been using and telling others to use. Since I am guilty of pushing some of these without the comma I know, at least, those would have been prevented.
>
> There is no specification for the format of the %YEARS% variable, so rather than showing a comma after %YEARS% shouldn't something specify that %YEARS% is either:
>
> MMMM,
>
> or
>
> MMMM, NNNN,
>
> else we risk users of the template using eg 2006-2013

Come up with a meaningful update to the current templates.

Changing this CR to reflect what enhancement is really needed to prevent the typos in the Oracle. copyright line.