RFR 8136645: jlink tool should create windows os compatible launcher

[Alan Bateman]

On 01/04/2016 06:27, Sundararajan Athijegannathan wrote:
> That is true of shell scripts too. i.e., existing code generates shell
> scripts on Windows too  (although those shell scripts seem to run fine
> under Cygwin).
>
> Do you think we should filter out? Cross-platform image generation scenario?
>
As I recall, the .sh is generated on Windows for those that might run it 
from Cygwin so I think okay to leave that. The main thing is only 
generate the .bat on Windows.

I think we can rid of the !Files.exists test for both the shell and .bat 
case.

-Alan.