Splitting string that contains consecutive delimiters

[moltenform]

Expected behavior:
split("a SPLITSPLIT b", "SPLIT") ---> ["a ", "", " b"]
Observed behavior:
split("a SPLITSPLIT b", "SPLIT") ---> ["a ", "SPLIT b"]
Within the loop in bsplitstrcb, i is sent too far forward
upon finding a match. Here is a proposed fix including tests,
open to suggestions. A few more details in the GH pull request.

[moltenform]

Splitting string containing consecutive delimiters gives unexpected results

Expected behavior:
split("a SPLITSPLIT b", "SPLIT") ---> ["a ", "", " b"]
Observed behavior:
split("a SPLITSPLIT b", "SPLIT") ---> ["a ", "SPLIT b"]

For me, this is not the expected behavior.
It seems to not correspond with the behavior when a single char delimiter is used,
split("a || b", "|") ---> ["a ", "", " b"]
(Note that the string gets sent to bsplitcb when delim is one char.)
Also, the behavior does not correspond with JavaScript, Python, etc. split().

Precise example:
struct tagbstring delim = bsStatic("aa");
struct tagbstring s = bsStatic("1aaaa1");
bstrlist *list = bsplitstr(s, delim);
list is ["1", "aa1"] instead of ["1", "", "", "1"]

Proposed fix attached, but open to suggestions