RFR [6943190] TEST_BUG: java/lang/Runtime/exec/ExecWithInput.java hardcodes path to cat

[Ivan Gerasimov]

Here's the (hopefully final) polished webrev: removed 'othervm' and 
replaced stderr with stdout in reporting of the wrong OS.

Would you please take a look?

http://cr.openjdk.java.net/~igerasim/6943190/4/webrev/

Sincerely yours,
Ivan