Remove sodium_compare() from the documentation

helpers/README.md

@@ -67,19 +67,3 @@ It runs in constant-time for a given length, and considers the number to be enco
 
 This function was introduced in libsodium 1.0.4.
 
-## Comparing large numbers
-
-```c
-int sodium_compare(const unsigned char *b1_, const unsigned char *b2, size_t len);
-```
-The `sodium_compare()` function returns `-1` if `b1_`, as a number encoded in little-endian format, is lower than `b2_`.
-
-It returns `1` if, using the same encoding, `b1_` is greater than `b2_`.
-
-Finally, it returns `0` if `b1_` and `b2_` are identical.
-
-This function can be used to compare nonces and counters in constant time.
-
-In order to check only for equality, `sodium_memcmp()` is preferred, as it is faster.
-
-`sodium_compare()` was introduced in libsodium 1.0.4.