Php_codesniffer: Add option to force all errors to display, even within @codingStandardsIgnore sections

[davidscotson]

If you're running CodeSniffer against code written by other people, you might want to get a full report of potential issues without giving them the ability to suppress any errors by using // @codingStandardsIgnore comments to skip files, or lines.

Reading through the docs there doesn't seem to be an override setting that allow this level of reporting.

[gsherwood]

I've added an --ignore-annotations CLI argument to ignore all @codingStandard... code comments. You can also set this value in a ruleset.xml file if you don't want to allow these annotations in your coding standard.