NULLTRIM
Name
	NULLTRIM
Purpose
	Trim a string of all characters after and including the first null
Explanation
	The null character is an ascii 0b
Calling Sequence
	result = nulltrim( st )
Inputs
	st = input string
Outputs
	trimmed string returned as the function value.
History
	D. Lindler  July, 1987
	Converted to IDL V5.0   W. Landsman   September 1997