RFR(S/M): 8144246: CompilerControl: adding lots of directives via jcmd may produce OOM crash

[Nils Eliasson]

Hi,

Please review this minor change. It introduced a limit to how many 
directives can be added. The limit can be controlled by the diagnostic 
flag CompilerDirectivesLimit. For normal use it would be very unusual to 
have more than a few directives.

The Flag PrintCompilerDirectives was changed to CompilerDirectivesPrint 
to have a consistent naming for all directives flag. This is a new flag 
and is not used anywhere yet.

Testing:
All the compiler control tests will have been run before submit.

Bug: https://bugs.openjdk.java.net/browse/JDK-8144246
Webrev: http://cr.openjdk.java.net/~neliasso/8144246/webrev.01/

Regards,
Nils