Add greek as lang definition in installer.
Developed in collaboration with Giannis Kourmoulis <ikourmou@lib.auth.gr>
Test plan :
- Install using "gr" in "Primary language for Zebra indexing"
- check gr is used in etc/zebradb/zebra-*.cfg
Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>