Mixlib CLI - Preserve ARGV after @opt_parser.parse!

Here:
http://github.com/dreamcat4/mixlib-cli/tree/CHEF-828

Hi, Dreamcat. We like this patch, and we see the use case. What we're nervous about is that we know there are likely some places in Chef/Ohai and friends that rely on the destructive behaviour, and we're not clear where they are all lurking. As we're very close to release, we're going to push this ticket out to the next release, and ensure it gets enough time to incubate.

My apologies for taking so long to post this update, but we'll get this in.

This ticket is a dependancy for COOK-245

As Adam said - this is less priority than 0.8 work. Actually this 828 fix also requires a re-release of the Mixlib-Cli gem (on gems.opscode.com) too.
But we would really like someone else familiar with Chef/Ohai sources to come forward to check the code. Meaning grep for the all references on ARGV.

This is just to be sure that there is no old code which implicitly assumes that ARGV must == 0. Although any early ARGV manipulation - before its given to the Mixlib mixin method "parse_options()" is absoloutely fine. Usually the parse_options method is called / overloaded from application.rb class.

This patch only prevents ARGV from being deleted by mixlib-cli processing. So generally other kinds of ARGV checks and manipulations are OK.

The applications that use mixlib-cli are:
chef-solo
chef-client
chef-solr
knife
ohai

Apps that don't use mixlib-cli manually parse their ARGV arguments. Or will use the optionparser parse! method directly.
They are unaffected. These are:
chef-server
chef-server (thor task)

These components all live in either the main chef repo, or the ohai repo (of course don't forget about ohai).

As for other components (not listed above), google has turned up nothing outside chef family that uses mixlib-cli.
Unless someone already knows of other gems (outside chef and not on github) that use mixlib-cli - well that seems unlikely.

rspec regression test added to my branch:
http://github.com/dreamcat4/mixlib-cli/tree/CHEF-828

ran rake features off commit 46617286f (chef March 04), to see that nothing has been broken. Came back fine (no new failures).

Results (rake features):
http://gist.github.com/323631

If theres anything further i can do to progress this ticket, please let me know.

Assigning over to Kallistec for comment

Bugs in parse_options return values break knife

Bugs have been resolved and pushed to master. Dan, please test/verify/close.

Adam, we need a version bump of Mixlib::Cli for this

This is done - thanks dreamcat for your advocacy, and Stephen for such great testing, and both of you for the final fix.

Cutting a new Mixlib::CLI now.