18663 - should be internationalized

Vendor the i18n gem at version 0.6.1 and update the gem spec to exclude
the vendored files and include the new dependency as a gem dependency
18663 - should be internationalized

Add basic i18n support to the logging system, locale information is
stored in $lib/mcollective/locales/en.yml - this location is not yet
configurable and we do not yet support setting your own locale.

At present the logging system supports logging standard messages:

   Log.logmsg(:MC001, :info, :version => "1.2.3", :name => $0)

This will parse a message from the local database that looks like:

   MC001: Started mcollective %{version} by ${name}

The locale database also support MC001_example and MC001_expanded which
would hold a sample error message and expanded text showing the
background for this message.

Logging of exceptions has been standardized:

  Log.logexception(:MC002, :error, :e => exception, :other => "data")

This will log the message in MC002 while interprolating %{error} into
the resulting text, other data will also be passed into the string

An application was added to support showing details on the error
messages and eventually the whole 'mco plugin doc *' functionality will
move into this application

   mco doc MC001