3.5.27 `string-contains-eqv?' - caseless substring

Usage: (*=* text match)
string-contains-eqv?: Test to see if a string contains an equivalent string. `equivalent' means the strings match, but without regard to character case and certain characters are considered `equivalent'. Viz., '-', '_' and '^' are equivalent.

Arguments:
text - text to test for pattern
match - pattern/substring to search for