refactored helper methods for VL (weight, images, etc)
Moved to_csv into PostType module
Renamed Property to Properties
Added Property class
Refactored Property; removed instance variables
Added validate_options! as class method
Setting invalid property type raises an error
refactored csv formatters using refinements
Added some comments
Merge branch 'properties' into develop

* properties:
  Added some comments
  refactored csv formatters using refinements
  Setting invalid property type raises an error
  Added validate_options! as class method
  Refactored Property; removed instance variables
  Added Property class
  Renamed Property to Properties
updated readme
bump version to 1.3.0
Merge branch 'develop'

* develop:
  bump version to 1.3.0
  updated readme
  Added some comments
  refactored csv formatters using refinements
  Setting invalid property type raises an error
  Added validate_options! as class method
  Refactored Property; removed instance variables
  Added Property class
  Renamed Property to Properties
  Moved to_csv into PostType module
  refactored helper methods for VL (weight, images, etc)

Conflicts:
	lib/efo_nelfo/version.rb