updated readme
updated readme

Fixes #2431
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117823087

DavesMan/guava,tli2/guava,mosoft521/guava,google/guava,typetools/guava,berndhopp/guava,jakubmalek/guava,EdwardLee03/guava,Xaerxess/guava,xasx/guava,mosoft521/guava,berndhopp/guava,EdwardLee03/guava,google/guava,rgoldberg/guava,google/guava,rgoldberg/guava,mosoft521/guava,tli2/guava,Xaerxess/guava,jakubmalek/guava,DavesMan/guava,typetools/guava,xasx/guava