g_string memleak fix in recipe_handler and task_handler

g_strings should be freed regardles of whether they contain actual data or not.
xmlparser free order fix in recipe_handler()

xmlDocPtr should be freed before xmlParserCtxt, not the other way around.
Merge pull request #6 from sm00th/g_string_memleak

g_string memleak fix in recipe_handler and task_handler
Merge pull request #7 from sm00th/xmlparser_free_order

xmlparser free order fix in recipe_handler()