Improved support for regex capture group names

[Baaaaaz]

closes #5959

Description of the Change

• Changed stringFind() method:
  • named capture groups present in the regex pattern are now stored as a variable
  • group matches are also now stored as variables using the related group name (meaning existing getGroup...() functions also now work with capture group names passed to strFind()).
  • slight refactoring for clarity and to reduce repetition in string concatenation.
• New getGroupNames() MTScript function:
  • args: id
  • returns a JSON object of mapping named capture groups present in the regex pattern to their group indexes
• New json.fromStrFind() MTScript function:
  • args: string, pattern [, returnNamedGroups (default = false) [, returnGroup0 (default = false)]]
  • matches the pattern against the input string and returns a Json array of objects with capture groups as keys and matches as values

Possible Drawbacks

For stringFind() if capture group names are used in the regex, stored matches are duplicated in variables referenced by either index or by name.

Documentation Notes

t.b.c.

Release Notes

Improved support for regex capture group names

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