Fix bias overflow in Remove_Series

bias is 16-bit, and len is 32-bit, so check overflow before modifing
bias.

This fixes the crash:
a: copy ""
insert/dup a #"a" to integer! #10ffff
take/part a 3
take/part a to integer! #f0010

insert/dup a #"b" 10
a: 1 ;force a to recycle
recycle
print a
Check overflow in integer literals

Make this:
>> 9'999'999'999'999'999'999
== 9223372036854775807

become:
>> 9'999'999'999'999'999'999
** Syntax error: invalid "integer" -- "9'999'999'999'999'999'999"
** Near: (line 1) 9'999'999'999'999'999'999

https://github.com/zsx/r3/issues/8
Merge branch 'atronix' into serial