Updates kiji-schema requirement to 1.2.1.
Updates kiji-schema requirement to 1.2.1.

Reviewed by: Aaron Kimball <aaron@wibidata.com>

iafek/kiji-mapreduce,kijiproject/kiji-mapreduce,kijiproject/kiji-mapreduce,iafek/kiji-mapreduce,kijiproject/kiji-mapreduce