Follow naming convention.

slapos/recipe/wrapper.py

@@ -35,7 +35,7 @@ class Recipe(GenericBaseRecipe):
         wrapper_path = self.options['wrapper-path']
         wait_files = self.options.get('wait-for-files')
         environment = self.options.get('environment')
-        parameters_extra = self.options.get('parameters_extra')
+        parameters_extra = self.options.get('parameters-extra')
 
         if not wait_files and not environment:
           # Create a simple wrapper as shell script

software/jio/instance.cfg.in

@@ -46,4 +46,4 @@ LD_LIBRARY_PATH = ${libxslt:location}/lib:${libxml2:location}/lib:${zlib:locatio
 recipe = slapos.cookbook:wrapper
 command-line = ${phantomjs:location}/phantomjs-slapos
 wrapper-path = $${directory:bin}/phantomjs
-parameters_extra = true
+parameters-extra = true