Turning `header` patterns into `signature` patterns in all syntax files
was a mistake. The two are different things. In almost all syntax files
those patterns are things like shebangs or <?xml ... ?> or
<!DOCTYPE html5> i.e. things that:
1. can be (and should be) used for detecting the filetype when there is
no `filename` match (and that is actually the purpose of those
patterns, so it's a regression that it doesn't work anymore).
2. should only occur in the first line of the file, not in the first
100 lines or so.
In other words, the old `header` semantics was exactly what was needed
for those filetypes, while the new `signature` semantics makes little
sense for them.
So replace `signature` back with `header` in most syntax files. Keep
`signature` only in C++ and Objective-C syntax files, for which it was
actually introduced.
* highlighter: Fix regions and patterns inside regions
* highlighting: Remove 2nd recursive highlightRegion() call
...and add limitGroup checks to pattern search.
* yaml: Add TODO type highlighting
* highlighting: Don't stop in highlightRegion() at empty lines
...because possible region line end pattern must be detected.
* syntax/sh: Correct string handling due to additional pattern handling
* syntax/sh: Remove slash in variables
* highlighter: Accept nested region only in case it's within the current reagion
* highlighter: Accept nested patterns only in case it's within the current reagion
* highlighter: Don't search for nesting in case the region end was found at start
* 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
Make the regular expression much more precise:
* match literal dots instead of any char (match rc.conf but not rcXconf)
* match special filenames exactly (match PKGBUILD but not myPKGBUILD.something)
Run build-all to update internal/config/runtime.go
closes#2163
Use the 'regexp2' library for lookahead and lookbehind in region
start and end regular expressions to support things like closing quotes
that aren't preceded by backslashes.
