Format fix 2012/vik/README.md + add alt code

Based on the author's description I made an alt version that should
theoretically work in Windows though of course (thank goodness) I have
no way to actually test it.

Just like with 2011/vik I've only done this because part of issue #1 is
to make entries work on as many systems as possible though it's not
entirely clear to me that 'Windows' should even be considered a 'system'
at all let alone one worthy of consideration :-)

Updated .gitignore.

2012/vik/Makefile

@@ -112,8 +112,8 @@ OBJ= ${PROG}.o
 DATA= chocolate.png ioccc.png
 TARGET= ${PROG}
 #
-ALT_OBJ=
-ALT_TARGET=
+ALT_OBJ= ${PROG}.alt.o
+ALT_TARGET= ${PROG}.alt
 
 
 #################