[IBL] new grs program (3.1.0)

[Sean Sweda]

I've updated the grs program, changes include:

3.1.0	* track batters faced (BF)
	* display current pitcher's IP & BF totals
	* prevent overwriting of existing output files
	* check for valid defensive lineup
	* fix undo after dc bug

I also added codes for some relatively obscure events:
ri - baserunner out due to interference
di - defensive indifference
tp - triple play

source now available on github -> https://github.com/seansweda/grs

Rusty was kind enough to create a Windows/DOS executable.  I've put it here:
ftp://ftp.ibl.org/grs/grs-3.1.0/GRS.EXE

Sean