Do not autocomplete after finishing a percentage

[50Wliu]

Requirements

• 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

Description of the Change

Do not autocomplete property values here: width: 100%|.

Alternate Designs

Adjusting ac+'s default prefix to include the percentage sign.

Benefits

No useless completions after a percent.

Possible Drawbacks

None?

Applicable Issues

Fixes #96

[sebszocinski]

I've just noticed this fix is only applying to the percentage key like my original issue 96 but I commented an update saying it's actually on any modifier key or even a comma... eg:

[50Wliu]

It is expected that completions happen after a comma because it's a list separator. As for the others...if you can provide an example of where those would show up in a CSS file that would mess up autocompletions, I'll take a look. As it is, I'm having trouble imagining seeing those in a CSS file.