Coroutines are not supported (aka asyncio)

[ticosax]

Hi,
It seems asyncio's coroutines are not supported.

$ frosted -r -vb project
Traceback (most recent call last):
  File "/home/nicolas/.virtualenvs/project/bin/frosted", line 11, in <module>
    sys.exit(main())
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/main.py", line 38, in main
    warnings = check_recursive(file_names, **arguments)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/api.py", line 152, in check_recursive
    warnings += check_path(source_path, reporter, settings_path=None, **setting_overrides)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/api.py", line 133, in check_path
    return check(codestr, filename, reporter, settings_path, **setting_overrides)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/api.py", line 114, in check
    w = checker.Checker(tree, filename, None, ignore_lines=_noqa_lines(codeString), **active_settings)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/checker.py", line 265, in __init__
    self.handle_children(tree)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/checker.py", line 520, in handle_children
    self.handleNode(node, tree)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/checker.py", line 553, in handleNode
    handler(node)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/checker.py", line 838, in CLASSDEF
    self.handleNode(stmt, node)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/checker.py", line 552, in handleNode
    handler = self.get_node_handler(node.__class__)
  File "/home/nicolas/.virtualenvs/project/lib/python3.5/site-packages/frosted/checker.py", line 435, in get_node_handler
    self._node_handlers[node_class] = handler = getattr(self, nodeType)
AttributeError: 'Checker' object has no attribute 'ASYNCFUNCTIONDEF'
make: *** [check_frosted] Error 1

The kind of code we are writing looks like this.

async def do_something():
    return await do_another_thing()