fix --prepend option of the render command causes NoMethodError
Merge pull request #99 from co3k/fix-render-prepend

fix --prepend option of the render command causes NoMethodError
fix tests to match new combine functionality
[render] further simplify interface

template now just receives options and schema as input
fix links to properly reference ref_resource
upcase variables in curl examples
stripping excess whitespace in template
remove leading whitespace from template
[templates] ensure consistent ordering for extract_attributes