optscript: minor issues

[masatake]

Interpreter:

• provide the way to fill language specific fields
• provide the way to create anonymous tags
• provide accessors for implementation field
• revise the original {_field=} feature
• _strrpbrk
• write a tutorial
• options fo listing error types.
• provide operators to specify locations (_matchloc)
• accessor for table execution stack
• provide the way to run guest parsers (_makepromise)
• provide accessors for access field (:access, access:)
• provide accessors for file field
• provide accessors for pattern field
• implement \0
• Assert() alike operator

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Improve parsers:

• rewrite puppetManifest parser. See PuppetManifest: minor improvements #2974. (partially done)
• operator for setting placeholder flag (in progress main: introduce --_makeTagEntryReflection-<LANG> option to filter tags #3027)
• Implement Vue
• Imporove Elm parser