Merge branch 'release/v0.10.0' into develop

* release/v0.10.0:
  Version bump to v0.10.0 and regenerated gemspec.
GirlFridayAsync now rescues Serf::Errors::NotFound.

Details:
* GirlFriday pumped out a lot of error messages because of notfound.
  Worker block changed to capture the error, which suppresses the messages.
GirlFridayAsync no longer assume Hashie::Mash input.

Details:
* Changed from method style access to parameters to dictionary []
  access w/ symbols.
* This provides benefit in case the ENV passed in was not a Hashie Mash.
Updated doc about async background processing.
Changed error class inflection; added ruby ENV.

Details:
* Added ENV.to_hash to the caught_exception_event message.
  This contains more info about how the process was launched.
  Can possibly contain the code's "Git Hash" to version which
  code is being run.
* Removed the reliance of ActiveSupport string inflections to
  describe the raised error. Back to "MyModule::MyError".
Rename context to headers; Remove ErrorHandling from Command.

Details:
* Slight semantic change that the context is really the
  headers to the message. The combination of which is a "Parcel".
* Remove the ErrorHandling module from the Command module.
Rename "message" to "dict".

Details:
* Uuidable may annotate more than just messages. It can do the
  "headers" object too. Thus we rename the variables message
  to "dict" since any hash like object can be used.
Rename "context" to "headers" in routing.

Details:
* Everything works the same, we just renamed context to headers
  in the routing code.
Uuidable: Works even if parent is 'nil'.

Details:
* 'parent' method parameter is default to {} if it was not set, but Uuidable
  methods may be called with explicit nil. It crashed before.
* Change now sets 'parent' to nil by default, and will survive by
  initializing an empty hash if parent was called implicitly or
  explicitly with a nil.
Fix: Command's default 'call' method parames.

Details:
* Missing comma in method parameters definitiion.
* Also Remove Unused ActiveSupport Class Attribute.
Big Summer Semantic Change

Details:
* Changes how commands and serf apps are called.
    Command.call(headers, message)
    SerfApp.call(headers, message)
  Note that we have explicit headers and message.
* UUIDs are moved from the message into the headers.
  The thinking is message is just solely about the business domain.
  UUIDs are about tracking requests and messages, which is about processing
  flow instead of business logic.
* Removed async handling middleware.
  The built serf app is just a quick in and out of requests and responses.
* Removed the request, response and error channels.
  We may re-add them in later for audit logging in a different commit.
* Error handling won't push to an error channel. Instead it will just
  wrap the raised exception into a message to be passed back.
  This will allow us to handle error and normal events
  in a uniform manner for a future response channel.
* uuidtagger fixes past problems about uuid tagging (missing origins,etc).
* we have a new policy_failure error message kind for policy failures
  instead of a generic caught exception.
* serfer class now guarantees that the executed command WILL have new
  readonly safe frozen Hashie::Mash for headers and messages.
  Hashie::Mash are deep copies of the input.
  This saves us from side effects between command calls for same request.
Removing outdated thread pool docs.

Details:
* Serf isn't directly handling threads right now.
Converts gemspec management from Jeweler to Bundler.

Details:
* Updated .gitignore for vendor/ruby for bundling install target
* Updated Gemfile to remove all "soft" dependencies.
* Updated Gemfile to remove jeweler
* Updated Rakefile to remove jeweler tasks for building gemspecs, etc
* Updated serf.gemspec to be manually maintained, simplified.
Updated README w/ clarified objectives of Serf.

Details:
* Listed lots of source material that inspired the evolution of Serf.
* Clarified the different parts of a Serf app.
Added ice_nine requirement for freezing Hashies.

Details:
* ice_nine for deep freezing the headers and message. >= 0.4.0
* also updated ActiveSupport version to >= 3.2.8
* also updated uuidtools version to >= 2.1.3
Adds ParcelTapper middleware for message passing.

Details:
* Serf was lacking the message passing features that it once had
  for the request and response messages.
* ParcelTapper is a middleware to drive the pushing of these messages
  onto messaging channels.
Fix reference mistake between EIP and PEAA books.
Add custom data to Serf::Errors::NotFound.

Details:
* Passes along the request headers and request message.
* The custom to_s will print out the kind and uuid of request.
Return Not found event instead of raising exception.

Details:
* Keeping the Serf::Errors::NotFound error just because,
  but instead of raising the error, we're going to return an error
  event of 'serf/errors/not_found'.
Removing .document and .rspec.

Details:
* Not using external services that uses them.
* Keep the tree cleaner.