Update es_ES.lang

Hi, i am Juput, and i will be translating (correctly) this mod from en_EU to es_ES. What have i done today is; Correct all the "Oxigeno" for "Oxígeno" also fixed some mayor spanish grammar errors and translated some other stuff... will time, i will get it all done :)
Merge pull request #801 from Juput/patch-1

Update es_ES.lang