Open code review for 8061999 Enhance VM option parsing to allow options to be specified

[Ron Durbin]

Here is the round 1 webrev for 8061999. It incorporates changes made
due to comments from the round 0 reviewers. The easiest way to review
this round is to download the two patch files:

http://cr.openjdk.java.net/~rdurbin/8061999_OCR0_JDK9_webrev/hotspot.patch
http://cr.openjdk.java.net/~rdurbin/8061999_OCR1_JDK9_webrev/hotspot.patch

and look at them in your favorite file merge tool.

RFE request:
https://bugs.openjdk.java.net/browse/JDK-8061999

This RFE allows a file to be specified that holds VM Options that
would otherwise be specified on the command line or in an environment variable.
Only one options file may be specified on the command line and no options file
may be specified in either of the following environment variables
"JAVA_TOOL_OPTIONS" or "_JAVA_OPTIONS". 

The options file feature supports all VM options currently supported on
the command line, except the options file option. The option to specify an
options file is "-XX:VMOptionsFile=<Filename>".
The options file feature supports an options file up to 1024 bytes in size
and up to 64 options.

This feature has been tested on:
  OS:
    Solaris, MAC, Windows, Linux
  Tests:
    Manual unit tests
    JPRT with -testset hotspot (including the SQE proposed test coverage for this feature.)