Refactors setting of parameters in API DSL

* removes ParameterMethods module, functionality is integrated in ParamBuilder
* refactors specs to used shared example
Refactors and extracts common set up to private method
Adds UrlBuilder specs and removes unnecessary tests

* UrlBuilder class is now tested
* fixes DSL specs
Refactors erb template to output class with DSL statements
Fixes API specs
Adds a more complete example with tests
Adds specs to cover DSL paths functionality

* refactors setting of attributes in DSL classes
* adds specs for `path` method
* reorganized specs for params
Fixes number parameter method
Adds time parameter to DSL
Adjusts example with params in test set up
Adds parameter output to ERB template
Refactors setting of base path in DSL

* adjusts template accordingly to set url path
* adjusts specs to take base path as argument when calling `url` block into account