Bootcamp and Windows 8 Installed, no option to boot from partition
I had the same issue, this fixed it for me:

sudo fdisk -e /dev/disk0
flag 4
write
exit


Apparently it wasn't flagged as active:
http://www.reddit.com/r/mac/comments/2eo7dq/win7_bootcamp_hd_not_showing_up_as_startup_disk/