:sig
String nibble(String& haystack, String delim)

:params
haystack : string to be nibbled at
delim : delimiter
return value : string before first occurrence of 'delim'

:desc
Returns the part of 'haystack' before the first occurrence of 'delim', removing the corresponding part from 'haystack' (including 'delim'). If the substring 'delim' does not occurr in 'haystack', the entire string is returned and 'haystack' is set to an empty string.

:see
>string