* highlighter: Fix region & pattern detection
* syntax/sh: Highlight upper case options too
* syntax/c(pp): Try to synchronize the rules to lower the maintenance effort
* syntax/ruby: Fix explicit filename detection in directories
* highlighter: Respect skip rules in regions
* syntax/sh: Fix parameter expansion, cond. flags and generalize filename via ""
* syntax/php|vi: Correct strings in comments to comments only
Additionally improve vimscript comment handling.
* highlighter: Remove problematic start|end check in find(all)Index()
...and additionally remove recursive region end detection
* Add enum keyword to PHP (8.1) syntax
* Specify only keywords that are valid as type declarations as PHP types
boolean, integer and resource are not valid type name.
* Add match keyword to PHP (8.2) syntax
