Updating the Evaluation order section to cover *expression in calls

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2018-05-14.08:14:24.843>
labels = ['3.7', '3.8', 'docs']
title = 'Updating the Evaluation order section to cover *expression in calls'
updated_at = <Date 2018-05-18.17:36:41.856>
user = 'https://github.com/mjpieters'

bugs.python.org fields:

activity = <Date 2018-05-18.17:36:41.856>
actor = 'terry.reedy'
assignee = 'docs@python'
closed = False
closed_date = None
closer = None
components = ['Documentation']
creation = <Date 2018-05-14.08:14:24.843>
creator = 'mjpieters'
dependencies = []
files = []
hgrepos = []
issue_num = 33492
keywords = []
message_count = 1.0
messages = ['316494']
nosy_count = 3.0
nosy_names = ['mjpieters', 'docs@python', 'Eric Lebigot']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = None
url = 'https://bugs.python.org/issue33492'
versions = ['Python 3.6', 'Python 3.7', 'Python 3.8']