Allows to set text parameter in DSL, works same as string
Adds test to cover unknown parameter type
Adds multi_index function to PartBuilder
Namespace defaults to 'core' if spec files are missing one

This puts all generated ruby files into a `core` folder if the source JSON files are missing a prefix.
Changes setting of base path in url block
Fixes creation of module name

* adds specs
DSL allows to set source parameters
Adds Core namespace correctly if JSON file does not contain a namespace

* adjusts tests accordingly
Require all ruby files in eson/shared folder
Renamed template to description.erb as it describes api endpoint
Adds another command to create http request ruby files
Simplifies description ERB template
Adds http request ERB template
Extends request command to write HTTP request ruby files
Extends Readme with information about how to run the CLI tool

* adds description for CLI commands to generate ruby files