Add Steven Danna as a maintainer of Dev Tools

I've fixed a number of chef-shell and knife related bugs, written a
number of popular knife plugins that build on top of these systems,
and understand the related code well.
Remove all parts of 'shef'
Merge pull request #2485 from opscode/ssd/maintainer-app

Add Steven Danna as a maintainer of Dev Tools
Adding myself to relevant component maintainer
Merge pull request #2490 from jtimberman/jtimberman/maintainers

Adding myself to relevant component maintainer
Adding myself as a maintainer
Fixing formatting
Merge pull request #2510 from opscode/tball/maintainer

Adding myself as a maintainer
Add Seth Vargo as LT for ChefSpec
Merge pull request #2499 from juliandunn/trash-shef

Remove all parts of 'shef'
A memorial for Ezra Zygmuntowicz

Adding the --ez switch to Chef Solo, to memorialize Ezra. He was the
father of Chef Solo, and without his early advocacy and evangelism,
there would be no Chef today.

Rest in peace, Ez.
Add myself to MAINTAINERS
adding myself to MAINTAINERS
Use lists.
Add myself as a core maintainer.
Merge pull request #2526 from opscode/mcquin/maintainer

Make me a maintainer
Merge pull request #2516 from adamhjk/ez-mode

A memorial for Ezra Zygmuntowicz
Remove unused "agent".
This was probably an aborted attempt to integrate this project into Chef:
https://github.com/opscode/opscode-agent
Fix knife plugin path searching

Unreleased Chef 12.0.0 bug caught in testing where only the searching
upwards from PWD to find .chef in order to get the plugin path for knife
was busted.  The chef_config_dir was being used before load_config was
being called, so it was nil, which broke finding knife plugins.  This
was fixed by adding some lazy initialization of the config_loader object
itself and the chef_config_dir.

The reset_config_loader! is added entirely to reset the global state for unit
testing.  This whole class is a bit horrible and needs to have all its
global state removed from it, class methods removed, class ivars and the
class-variable-in-a-class-method-for-inheritance-lolwut needs to be removed.

Unfortunately, that requires some delicate surgery because Chef::Knife
gets used as a public API, and is beyond the scope of gettting Chef 12
shipped.
Merge pull request #2527 from opscode/lcg/knife-plugin-fix

fix searching upwards for knife plugins