Description:
------------
The parameter case_sensitivity should probably be named case_insensitivity in the documentation.

"int substr_compare ( string main_str, string str, int offset [, int length [, bool case_sensitivity]])"

and

"If case_sensitivity is TRUE, comparison is case sensitive."


Reproduce code:
---------------
print substr_compare("abc", "ABC", 0, 3, TRUE);
print substr_compare("abc", "ABC", 0, 3, FALSE);

Expected result:
----------------
1
0

Actual result:
--------------
0
1