RFR: JDK-8007897 Problems cleaning up a file named jdk/gensrc/java/nio/_the.. on Windows

[Tim Bell]

Hi Magnus:

> During build, we create a touch file which is literally named 
> '_the..'. While cygwin handles this without issues, Windows believes 
> this to be a file with the extension "." and can't touch it, that is, 
> not delete or move it.
>
> This patch renames this file (and others created at the same time) to 
> have a proper extension (".marker"), which Windows deals with properly.
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8007897
> WebRev: 
> http://cr.openjdk.java.net/~ihse/JDK-8007897-make-file-has-illegal-name-in-window/webrev.01

Looks good to me.  Thanks for fixing this.

Tim