Added async (line 851)

[ThatXliner]

Added keyword async:

 'illegal_names':
    'match': '\\b(and|as|assert|break|class|continue|def|del|elif|else|except|exec|finally|for|from|global|if|import|in|is|lambda|nonlocal|not|or|pass|print|raise|return|try|while|with|yield|await|async)\\b'
    'name': 'invalid.illegal.name.python'

Requirements

• [X] Filling out the template is required. Any pull request that does not include enough information to be reviewed in a timely manner may be closed at the maintainers' discretion.
• [ ] All new code requires tests to ensure against regressions (Does Travis-ci count?)

Description of the Change

Alternate Designs

Benefits

• People are less likely going to use reserved names for asynchronous stuff

Possible Drawbacks

Code that already uses async as a variable name will be highlighted differently

Applicable Issues