Splits an id in the toolset and specific rule parts. E.g.
        'gcc.compile.c++' returns ('gcc', 'compile.c++')

def split_action_id (id):
    """ Splits an id in the toolset and specific rule parts. E.g.
        'gcc.compile.c++' returns ('gcc', 'compile.c++')
    """
    assert isinstance(id, basestring)
    split = id.split ('.', 1)
    toolset = split [0]
    name = ''
    if len (split) > 1:
        name = split [1]
    return (toolset, name)