Added ActiveModel 2.3.13 depenendency
Merge branch 'master' into base
Clerk::Base and ActiveModel dependency

- Created a Base class for Clerk models/objects/clerks to inherit
- Added ActiveModel dependency for Validations, Serialization, and
  others
- Removed Clerk v1 code from lib/clerk.rb, this will live in modules
Removed Clerk::Base and created Clerk::AbstractParser

- Removed ::Base as it is no longer necessary, parsers will replace it
- Updated Clerk module to autoload ::AbstractParser instead of ::Base
- Added an AbstractParser to be inherited by the individual parsers
- Updated Gemspec
Adding a very basic Clerk::Template DSL

The basic templating DSL for Clerk will allow named, ignored,
and grouped elements. This commit has the very basic implementation
of those particular types of structural indicators.
Expanding named to support positional assignment

Expanding the named keyword to support adding a named element in
a specific order or from a specific position in the input data.
For example if you wanted to assign the second column of input to
the named paramter :b you would assign it as follows.

  t.named :b, :position => 2

Which would then result in a template of [nil, :b]
Merge branch 'template-dsl' of github.com:liftopia/clerk-gem into base
Back to Clerk::Base!

After a morning discussion with Paul and Jeff it seems that Clerk::Base
makes the most sense in separating our concerns

- Created ::Base to serve as the foundation for Clerks
- ::Parser contains a registry of available parsing implements
- ::Base has a parser option that accepts a Symbol, String, or Class
  (not instance)
- ::Base handles validation, serialization, callbacks
- Created a super basic ::CSVParser object to work with
Autoload ::Parser, ::Template.  Fixed issue with ::Base configuration.

- Updated clerk.rb to autoload ::Template and ::Parser
- Fixed a bug in ::Base where parser and template were instance instead
  of class methods
- Fixed a bug with ::Parser.register with how class inherited is tested.
  Now it works without instantiating the object.
- Added a ? to contains method as it returns a boolean
WIP
Extracted the ParserRegistry functionality to a separate class; refactored code for registry change.
Fixed bug with earlier parser refactor changing load to parse.  Removed template logic
Lowercased the gem name like everyone else
Removed parser functionality from Clerk