feat: stringtheory.like(haystack text, search text) -> boolean

[wuputah]

This is a possible proposal to implement:

stringtheory.like(haystack text, search text) -> boolean

The implementation would only optimize only if search text is either: %foo% (substring), %foo (suffix), or foo% (prefix) search. Otherwise the implementation would fall back to the Postgres built-in LIKE search automatically.

Possible gotchas:

• %_foo% would not be supported, since _ means "matches any 1 character"
• %\_foo% is supported, since the backslash escapes the _.