kiji-scoring: EXP-420. Update to scala 2.10

issue: https://jira.kiji.org/browse/EXP-420
review: https://review.kiji.org/r/1708
commit: https://github.com/kijiproject/kiji-scoring/commit/5d1271aed3e0585e346f6f905b40bfbcb8d8715e
kiji-scoring-server: EXP-420. Update to scala 2.10

issue: https://jira.kiji.org/browse/EXP-420
review: https://review.kiji.org/r/1709
commit: https://github.com/kijiproject/kiji-scoring-server/commit/a29887d6ee8b45de15924edc15bdef56aa150491